I LIBRARY OF CONGRESS. 5 



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i UNITED STATES OF AMERICA, f 

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DR. FEUCHTWANGER'S 



Practical Treatise 



ON 



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J 



7 




/Silicates of Soda or Potash, J 

Its Application to Artificial Stone and to render 

Wood Fire and Rot-Proof; Containing the 

Latest Information for its use in Paints, 

Soap, Paper, Cements and Calico 

Printing. 

By Dr. Lewis Feuchtw anger, 

CHEMIST AND MINERALOGIST. 



(it 



THIRD EDITION. 



NEW YORK : 

PUBLISHED BY L. FEUCHTWANGER & CO., 

No. 180 Fulton Street, 

1875. 



r^ 






Entered according to Act of Congress, in the Office of The Libbabian of 

Congress, by 

Dr. LEWIS FEUCHTWANGER, 
At Washington, the 17th day of September, in the year of our Lord 1875. 






A u " 



/\ 



Hiram Truss, Jr., Printer, 15 New Church St., N. Y. 



PREFACE 



TO THE PRESENT TREATISE. 



The objects of this condensed volume and the 
causes which induced the author for its issue, are the 
following i 

I. The two last Treatises of 1870 and 1873, giving 
a detailed description of the manufacture and uses of 
Soluble Glass, are this day entirely exhausted ; not 
having been stereotyped, there is not one copy left. 

II. The programme of both previous editions, the 
first containing additional treatises " On the Func- 
tions of Carbonic Acid and Origin of Limestone," and 
the last consisting in three practical treatises " On 
Soluble Glass, on Glass Making, and Guide on Soap 
Making," were deemed as exceeding the main object, 
and more advisable of touching solely on the appli- 
cation of Soluble Glass. 



IV PREFACE. 

III. The great improvement lately accomplished 
by the author in producing a neutral silicate which 
could answer all the purposes of painting, pasting, 
varnishing and soap making, without any efflor- 
escence of the alkali, is the main object of this publica- 
tion. 

IV. The price of the former editions was, by many 
applicants, considered too expensive, while the pre- 
sent edition can be supplied at a moderate price. 

Respectfully submitted by the author. 

Lewis Feuchtwanger. 



C O N T E N T S 



Page. 

Preface >»»■'».»,...■..%.»»»..%%».» 4 ..».»*».,'».»»»>,,« vii 

Treatise on Soluble Glass. , . . . „*.,'. 5 

The Uses of Soluble Glass, Silicate of Soda, Silicate of Potash, 

and Silicate of Soda and Potash , •. s . , , . 11 

Painting on Metals, Glass and Porcelain. > . . , * 32 

Stereochromic for Easel Painting, , k . , »» i ..,»».» » 37 

Silificatron of Wood — A Protection against Combustion, Inflam- 
mability and Dry Rot. .*■>..,,,-, t ..-,•..,.,,. -. * . . •> % . . -, > -. . v „ 39 
Drying Timber by Steam .,,,..*>...•,.>•* v. . ~. >,-..,, k .,.,,,> v w . 44 

Wooden Roof Shingles . ,, ■. » » . . » * ..,•.-.*,»,.. » .,.,..> v * . 46 

The Preservation of Wood by Immersion . „ 47 

Methods of Preserving Wood * 49 

Timber Rot and Seasoning. .»».■.•.»..»»...»...'%..■»»..%» 50 

Table of Analysis. ...... 52 

Street Pavements ........ 56 

On Mortar and Cements. .*»..»».«.. 61 

Common Mortar » . » * v , 6q 

Hydraulic Cement 70 

The Silicate Hydraulic Cement in the Prevention of Wall-damp 71 

Damp Walls and Cellars. . . 73 



■■i 



IV CONTENTS. 

Manufacture of Portland Cement 75 

Hydraulic Mortar from American Limestone 83 

German Hydraulic Cement . .' 87 

Cement and Mortar of the Ancients 88 

The Uses of Hydraulic Cement 92 

Silica Paints 99 

Soluble Glass in White Paints 103 

Soluble Glass in Colored Paints 105 

Black Paint 105 

Green Paints 106 

Blue Pigments 106 

Carmine 107 

Venetian Red 107 

Indian Red \cj 

Red Lead 107 

Light Red Earth 10S 

Yellow Colors 10S 

Yellow Ochre - 108 

Brown 108 

Sienna 108 

Umber 109 

Burnt Umber 109 

Van Dyke Brown 109 

Spanish Brown 109 

Silico Black Lead Fire Proof Paint no 

General Rules for the Uses of Soluble Glass in all kinds of 

Paints no 

Soluble glass for Black Boards and Silica Slates in 

Umber and Sienna Colors ill . 

Soluble Glass as a Coating for Wooden Floors. 112 

Practical Silicate Painting 113 

Painting on Metals, Glass and Porcelain 115 



CONTENTS. V 

The Best Permanent and Inerasible Ink 116 

Silicate of Soda in the Production of Gold, Silver and Aniline 

Inks . Il6 

A White Cement or Base for Inside Walls, Breweries and 

Cellars 118 

Silicate of Soda for Enamel 118 

Soluble Glass as a Medicine 119 

A Concrete Pavement. . 119 

Cements — The Most Adhesive Lubricator 120 

The Cheapest Silicate for Barns and Outhouses 121 

Luting for Gas Retorts 121 

A New Cement with Silicate of Soda 121 

Glazing of Pottery with Liquid Silicate 122 

Silicate Plastering 123 

Soluble Glass Application for Various Cements 124 

An Impermeable Cement Resisting Steam 125 

The Gypsum and Clay Cement 126 

Hard Adhesive Cement 126 

Cement for Closing Cracks in Stoves, etc., 127 

Cement for a Cistern 127 

The Soluble Glass as a Substitute for Glue 129 

The Soluble Glass in Calico Printing 130 

Silica Paint for Protecting Ships Bottoms 131 

The Most Durable Aquarium Cement 131 

The Soluble Glass as Manure for Grape Vines and Cereals 132 

A Strong Cement for Iron 133 

Iron Cement for Water and Gas Pipes and Castings 133 

Colored Cements 133 

Coating for Outside Walls 134 

Preservation of Stones from Green Coating 135 

Beton Building '. 136 

Soaps 137 



VI CONTENTS. 

The Silicate of Soda in Common or Household Soaps — Hard Soaps 140 

Tallow Soaps 142 

Tallow Rosin Soaps with Thirty-four Per Cent, of Soluble Glass. 144 
The Rosin Soaps with Twenty-four Per Cent, of Soluble Glas 

Liquid 145 

Cocoanut Oil Soaps with Twenty Per Cent. Soluble Glass Lie] aid 146 

Palm Oil Soaps and Addition of Twenty Per Cent. Silicate 147 

Different Soaps 148 

Various Soft Soaps which contain Fifty Per Cent. SUicate 14 •> 

Silicate Washing Fluid 151 

Silico-Tungstate of Soda 151 

Estimation of the Substances with which a Soap may be Adul- 
terated 1 5 2 

Table for Converting the Areometric Degrees of Baume into the 

Specific Weights of Liquids Heavier than Water 153 

Table for the Quanity of Caustic Soda in Soda Lye- 153 



TREATISE ON ■ 

SOLUBLE GLASS 

AND ITS MANIFOLD APPLICATIONS. 



The author has issued three separate editions on 
the above subject. They are all exhausted, and not 
having been stereotyped, for the reason that the 
advancement of science in this branch of practical 
chemistry and the daily improvements noticed in the 
journals of the increased uses of Soluble Glass in the 
arts, would make it more beneficial to the wants of the 
public, so as to communicate the latest discoveries 
and inventions, respecting it. The present issue com- 
prises in a practical point the most useful and reliable 
uses of Soluble Glass in domestic economy. For paints, 
artificial stone, cement, addition to soaps, or dunging- 
salt in calico printing, or fine printing material, and 
as mucilage, or sizing and filling for paper maker's the 
mode of application may all be relied upon. 

Soluble Glass or silicate of soda, called also 
liquid quartz or water glass, is, properly speaking, an 



6 SOLUBLE GLASS. 

alkaline silicate and may be combined with silica or 
silicie acid by either soda or potash, or with both 
alkalies. The composition is nearly the same as that 
of any other glass ; if combined with lime or potash 
it represents a good white flint glass, called the 
Bohemian Glass ; if with soda and lime, it forms the 
English crown glass ; if red lead is added to the mix- 
ture of silet and alkalies, a flint or crystal glass is 
obtained. The addition of alkali in certain quanti- 
ties produces either a soluble or insoluble compound. 
Our object is now to treat of the soluble compound 
or water glass, which has become of late years par- 
amounts in the arts, as its uses cannot be dispensed 
with ; and by naming only a few pursuits to which 
necessity taught us to apply it, it is obvious what 
a bright future is in store for its manifold application. s 
Recent events have turned the attraction of thought- 
ful men to a consideration of building material for 
the various public and private edifices. Wooden 
structures and those from the various mineral rocks, 
like granite, marble, brick and sandstones, have of 
late years been the subject of grave investigations. 
It appears proper that we no longer permit indis- 
criminate constructions to be raised, whereby the 
safety of a whole community is endangered, as we 
have had of late years sad experiences, when whole 
cities were laid waste by conflagration which might 
have been prevented if more cautions and safeguards 
had been properly applied, and millions of dollars 
worth of property could have been saved to owners 
and insurance companies. The time is now at hand 



SOLUBLE GLASS. 7 

when the character of building material is undergoing 
careful examination by builders, architects, under- 
writers and scientific experts. In order to fully ascer- 
tain whether wood, stone or iron may with safety be 
manufactured and constructed so as to prevent confla- 
grations and to make proper arrangements for extin- 
guishing any fires that may be produced either from 
incendiary or natural causes. 

"If people will insist upon constructing frame 
buildings in large towns, they ought to be compelled 
to render them essentially fireproof by the above 
chemical mixture. So many experiments have been 
tried with soluble glass, that the security it affords 
against fire and decay may be considered as fully 
determined. Wood thus prepared will char and 
smolder, but will not burst into flame ; and hence 
there could be no scattering of cinders or blowing 
about of firebrands. 

" In reference to the use of iron for houses, the 
fact that it is employed to a large extent, and that 
we are constantly acquiring greater skill in its mani- 
pulation and management, are sufficient proof of its 
practicability. In Chicago, however, this material 
proved unavailing, for the reason that the wooden 
structures made a fire hotter than a blast furnace 
constructed to melt pig iron. No iron could stand 
such a heat, and it melted down like wax. This 
was not the fault of the iron, but caused by the 
neglect to prepare the wood against such an emer- 
gency ; and no one will be likely to condemn iron 
structures on account of their failure in Chicago. 



8 SOLUBLE GLASS, 

" A third building material is stone, and this may 
be divided into native and artificial. There are a 
good many varieties of stone suitable for building 
purposes ; but the cost of quarrying, transportation 
and working, is so great in this country as almost to 
shut this material out of competition. This objec- 
tion does not apply to artificial stone. The lime and 
sand required to make artificial stone can be found 
nearly everywhere. They can be mixed by simple 
machinery, and require no labor to cut them into 
shape ; but the plastic material can be run into any 
kind of a mold, where it dries in a few hours, and one 
layer after another can be carried up in marvelously 
short time. 

" For rapidity of construction, for durability, for 
security against lire, for warmth and ventilation, for 
dryness and health, for economy, for architectural 
effects, there is nothing like artificial stone ; and we 
look upon this material as the most suitable for cities, 
and as probably destined to supersede all other. It 
only needs the popular dissemination of information 
on the subject to occasion a demand for artificial 
stone ; and as soon as such a demand is created, this 
material can be furnished in any quantity in all parts 
of the country ; and we shall have it for our cellars 
and our ice houses, our sewers, cisterns, wells, water 
pipes, paths, roads, schools, churches, dwelling houses 
and stores, in a way that will make us wonder how 
we ever performed the slow and tedious labor of 
hewing out stones or laying up brick, when we could 
have formed a whole house at one casting — as Krupp 



SOLUBLE GLASS. 9 

pours the melted steel into moulds, and produces a 
cannon of any size." 

It is generally known that the author was the 
first to introduce the soluble glass into the United 
States, and has devoted much time in experimenting 
with it ; and he has succeeded, after many fruitless 
trials, to create a demand in many branches of indus- 
try. From the extensive list of patents issued in 
Europe and the United States, he has collected all 
information, along with that obtained from the scien- 
tific and practical journals, and experimenters will 
find in this treatise the various uses and applications. 
Kulihnann s Pamphlet, the Mining and Engineering 
Journal, the Transactions of the American Institute, 
the Manufacturer and Builder, the Scientific Ameri- 
can, and the Annual of Scientific Discovery, have all 
furnished material for this treatise. 

Many interesting topics, such as the origin of salt- 
petre, the nitrate of soda, and the manufacture of 
blanc fix, had to be related, and will, no doubt, 
interest the general reader. 

Particular attention has been bestowed upon the 
formation of hydraulic cements and artificial stone, 
for the reason that more inquiries and experiments 
are performed in this branch than in any other of 
domestic economy. The natural stones, such as the 
brown stone, sandstone, limestone, and brick build- 
ing, will, sooner or later, after an exposure to the 
atmospheric elements, and rain and frost, become 
decomposed ; cracks and fissures will then produce 
the deterioration, while coated with the soluble glass 



IO SOLUBLE GLASS. 

and mixing the mortar with the same and impreg- 
nating the bricks, much is gained for their preserva- 
tion. 

It is somewhat remarkable, that long before this 
the art of making artificial stone has not been 
brought to perfection. Yet, if we may judge from 
the great and increasing variety of processes, patent- 
ed and otherwise, which now press their claims upon 
public notice, the time is ripe for the introduction of 
any process which can demonstrate practically its 
capacity to fulfill the requirements of the case. 
Every oppportunity has been afforded us to examine 
and test specimens of artificial stone, and we have 
met with many kinds, which have very little merit. 
Some, however, are really good stones, and, as such, 
must, in our opinion, come largely into use. 

The silicification of railroad sleepers, wooden rails 
and blocks for pavement is in importance next to 
the preparation of artificial stone. The comparison 
of the wooden and iron rails has also been clearly 
stated here, and the future will, no doubt, bring to 
light many facts here stated, but not yet put to prac- 
tice, The advantages of the wooden block pavement 
are numerous, and if properly laid, will withstand 
long years of the hardest kind of travel ; and there 
are but two important points in the wooden pave- 
ment to be observed, which are a firm and even 
foundation, and the good silicification of the founda- 
tion planks and blocks. 

The reason why the author has devoted so much 
space upon hydraulic limes, mortars, paints, white- 



SOLUBLE GLASS. II 

washes, and the preparation for guarding timber 
against dry rot and conflagration, is solely to prove 
and make it plausible that the application of soluble 
glass possesses great advantages, and may, with very 
little expense, give additional safeguards. 

Siemens recommends for the production of a white 
stone, to work up the fine silex with so much liquid 
soluble glass so as to form a plastic mass, say from 
three-fourth parts of the sand may be required, similar 
to potter's clay, and adding, at the same time, a small 
quantity of chalk and fine clay, whereby the mass 
becomes more uniform and compact. Prepared in 
this manner, objects moulded or pressed from the 
mass must be exposed to the air for some time. 

For monuments, millstones and other building 
material, he uses I part liquid silica to 2 parts fine 
sand, and 12 parts coarse sand, which mass, formed 
into the desired sizes or objects, after being dried 
long enough in the air, are left in a heated room of 
seventy-five degrees for several days, and even to the 
boiling point of water ; they become so hard, after a 
lapse of four to six days, that they never crack or fall 
to pieces. It is also recommended to expose the 
mass to the pressure of a hydraulic press before 
exposing to the air. For obtaining a cement — roofing 
and wall body — it is advisable to add the chloride of 
calcium to the mass, and thereby the excess of alkali 
is absorbed. 

The mass so formed may be steeped in a solution 
of chloride of calcium, or chloride of iron, before 
exposing to the atmosphere. In all these cases the 



12 SOLUBLE GLASS. 

silica ought to be employed very concentrated, even 
in jelly form. 

The uses of the soluble glass are here condensed 
in a short sketch, intended as a circular to those 
desirious of obtaining some information : 

" THE USES OF ^SOLUBLE GLASS (LIQUID SILEX) 
SILICATE OF SODA, SILICATE OF POTASH, SILI- 
CATE OF SODA AND POTASH (COMBINED.) 

" Liquid silica is now employed in the arts for 
many useful purposes, and particularly for preserving 
stone building from decomposition ; for preparing 
an artificial stone, and thereby reducing the price of 
building, and making a composition more ornamental. 
Its introduction for architecture is but of recent elate, 
and the true and proper method of application not 
yet on an infallible base ; but the subject is of so vast 
importance, that experiments are continually going 
on for making a perfect stone from its original 
ingredients. 

" The cause of gradual decomposition of building 
stone is attributed to the expansion and contraction 
of water absorbed, as well as to the chemical action 
of carbonic acid of the atmosphere, which abstracts 
•portions of the gases from the silicates, and liberating 
thereby silica. Many places in Europe, churches and 

* In the year 1832, Dr. F. prepared a quantity of Soluble Glass 
for the United States Government, to preserve the cannon, guns and 
bombs-shells from rust or oxy elation at the Navy Yard in Brooklyn, 
to the fullest satisfaction of the late Commodore Perry. 



SOLUBLE GLASS. / 1 3 

other public buildings, have been refinished by the 
silicate, such as the Louvre and Notre Dame Cathe- 
dral in Paris, the* Houses of Parliament in London, 
and in other cities. Still, its general application has 
met with many failures. It was found that rain 
counteracted the effect before the alkali has had time 
to take up a sufficient quantity of carbonic acid from 
the atmosphere and to liberate the insoluble silicate ; 
the coating will produce cracks, and a gradual disin- 
tegration of the surface or compound is caused there- 
by. Numerous remedies were suggested to counteract 
this evil — the chloride of calcium, oxychloride of 
magnesium, the bittern of salines, and hydrofluoric 
acid. At present a concrete stone of considerable 
hardness and durability is now prepared by means of 
greater pressure and proper manipulation, the main 
object being to neutralize and extract the alkali, and 
to form a solid chemical compound by a second 
application of a weak wash of chloride of calcium or 
magnesium. The object is not fully achieved. 

" Another important application of the soluble 
glass is to render wood non-inflammable, and to stop 
any communication of the fire, and at the same time 
proof against water and damp. The wood, timber or 
other substances, after being boiled for several hours 
in the soluble glass, then, exposed in tanks, contain- 
ing solution of lime water and solutions of chloride 
of calcium, are hereby petrified. 

" Railroad sleepers, cross-ties, house, ship and 
bridge timber, will also be silicified by this process. 
Telegraph poles become more durable and better 



14 SOLUBLE GLASS. 

non-conductors of electricity. The lining of barrels 
for oil and other liquids, the coating of tanks, tubs 
and cisterns, flour barrels, to prevent the flour getting 
musty, is very easy and effectually done by the 
proper and judicious use of liquid silica. 

" Soluble glass may be mixed with paper pulp, or 
cheap vegetable and animal fibre, and serve for the 
manufacture of a variety of useful articles, such as 
boxes, trunks, soles for boots and shoes, patterns, 
moulds and handles. Invaluable and of the highest 
usefulness, the soluble glass can be employed in fire- 
proof paints, cements, varnishes, etc., for which pur- 
poses the daily demands are sufficient proofs. 

" The dentists make use of the silica for mending 
their plaster moulds, or in case of an accident to the 
cast of a set of teeth. Valuable documents are made 
fireproof, and parchment board, slates and marbles 
are cemented together, and cracks and crevices filled 
up. 

" The wool growers apply the silicate of soda and 
potash to the greatest advantage for cleansing or 
degreasing the fleece wool and make it soft. . 

"The waste of wool or cotton used in the locomo- 
tive engines to sustain the lubricating materials, 
may be cleaned and made new by the aid of soluble 
glass. 

" A hard and ornamental cement, which can be 
moulded like plaster of Paris, is obtained from the 
mixture of silicate of soda and ground dolomite or 
magnesian limestone, which may be used both natural 
and calcined in equal quantities, and before the mass 



SOLUBLE GLASS. IS 

is dry, the bittern (chloride of magnesium,) from the 
salines is added, which will harden it at once. A 
good cellar and roofing cement is made by adding to 
this mass three parts of white sand. 

" The silicate is also used for penetrating fire-brick 
and clay, in order to make them more fire-proof, and 
also used for cementing the walls ; for producing a 
durable putty in iron castings, such as furnaces, 
heaters, stoves, etc., and also for mending air holes. 
Boiler makers can produce a very durable lining by 
making a cement of silicate with asbestos and man- 
ganese finely ground ; it renders boilers and other 
metallic vessels perfectly fire-proof, and the best fire 
and anti-rust paint for iron, steel and brass. There 
are a great many more useful applications in which 
the silicate may be used." 

The alkaline silicates, as have been here described, 
have a bright future for their application : the genius 
of the nineteenth century cannot fail to accomplish 
the perfecting the work begun fifty years ago, and to 
this moment still liable to faults. Ere long we will 
be enabled to produce an artificial stone which shall 
excel nature ; we will be able to produce a perfect 
silification of wood and other organic matter ; we 
will challenge the atmosphere and other chemical 
productions to do their best for forming a decompo- 
sition of these materials obtained by the newly ac- 
quired skill to resist their action. The labors of 
Fuchs, Liebig, Kuhlmann, Vicat, Fremy, Guerin and 
Ransome have fairly begun their work, and in ten 



1 6 SOLUBLE GLASS, 

years more the ship builder, carpenter, mason, 
painter, the railroad contractor, and the mechanic in 
general, will consider this valuable substance indis- 
pensable. 

The author has, many years ago, in the course of 
his experiments, succeeded in preparing an artificial 
stone in the following manner : — Fluorspar, finely 
ground, is mixed with the powdered soluble glass, 
two parts of the first to one part of the latter, the 
mixture made into a thin paste by the concentrated 
liquid soluble glass, and then as much finely pow- 
dered shell limestone, or magnesium limestone added, 
until the mass becomes thick enough to form into 
moulds or blocks, whichever may be desired ; after 
an exposure of three to four days to the atmosphere, 
are treated by a weak solution of chloride of calcium 
(two pounds dry chloride to the gallon of hot water), 
this liquid will soon be absorbed by the stone ; it is 
then exposed again to the atmosphere for a week ; 
a dilute hydrofluoric acid is then applied with a 
sponge, and again exposed to the atmosphere ; after 
a lapse of a week the stone is as hard as a natural 
stone, and not liable to crack or to disintegrate. 

This composition is much easier prepared, and 
instead of common lime chalk may be substituted, 
and the result is still more favorable. Instead of the 
entire quantity of lime, coarse sand may be partially 
added, and, after the stones are moulded, are exposed 
to hydraulic pressure, and then exposed to the air, 
previous to which the chloride of calcium has to be 
thrown over it. The price of hydro-fluoric acid, as 



SOLUBLE GLASS. 1 7 

is used lor this purpose, costs about twenty-five cents 
per pound, and this suffices for ten square feet. 

Furthermore, it may be remarked that exposing 
the stone so prepared may be subjected to a high 
temperature or not ; it may be left to the operator 
to decide whether it will improve the stone by this 
manipulation. 

For the sandstone imitation, when one part liquid 
soluble glass is. to be mixed with two parts powdered 
soluble glass, and fifteen parts of sand is added, it is 
necessary to expose the mass to great pressure, but 
requires not the addition of calcium, while exposure 
to great heat is indispensable. 

An artificial stone may be also obtained by the 
use of the alkaline silicates with common chalk, 
which, by mixing even cold with the liquid silica, is 
at once converted into silicate of lime and carbonate 
of soda or potash ; this composition, when exposed 
to the air, becomes in a few days hard enough, so as 
to resemble a hydraulic lime, to adhere, when wetted 
again, like a cement, which may be used for restoring 
cracks and crevices in marble works and monuments. 

The silicification of chalk has led to numerous 
experiments, and resulted in the production of arti- 
ficial stone, in the formation of hydraulic lime, 
hydraulic mortar, and the various cements. The 
first successful result of the treatment of chalk with 
the silicate solution has shown that the hardening 
of the chalk extended to the depth of four inches, 
which not alone was produced from the decomposi- 
tion of the silicate by the carbonate of lime (chalk), 



—._ 



1.8 SOLUBLE GLASS. 

but also by the carbonic acid of the atmosphere. If 
two balls of chalk of equal size and quality are silici- 
fied at the same time, and one of them is exposed to 
the atmosphere, the other kept under a bell glass, 
where the carbonic acid of the atmosphere is with- 
drawn, the first will acquire more hardness than the 
other, which proves that the silicification has assumed 
a hydrate of silica — carbonate of lime — which loses 
by degrees its water oi crystallization, and forming a 
precipitate of silica, contributing mainly to the 
hardening of the stone. 

A hydraulic lime may be obtained by the mixture 
of a fat or rich limestone combined with soluble glass 
in a dry state, say ten parts silicate to one hundred 
parts of air lime, both fine powder, which proves 
plainly the theory of the part which the silicates play 
in the production of the native limestone, the arti- 
ficial hydraulic lime, mortar, cements, and the appli- 
cation of all silicates for the purposes of building, 
production of artificial stones, and the conversion of 
organic into inorganic materials, as we shall show 
hereafter. 

Wood, paper, linen and straw, when covered with 
several coats of soluble glass, are no longer inflam- 
mable, but simply char when exposed to fire. It also 
prevents the decay and rotting of wood, and keeps 
out worms. Beer barrels, butter firkins and milk tubs 
can be easily kept clean when painted with soluble 
glass, and the same is true of vessels designed to 
hold sugars, syrups, wines, petroleum, etc. The 
most important use of soluble glass is its application 



SOLUBLE GLASS. IQ 

to surfaces of stone and mortar. For this purpose it 
is necessary to impregnate the surface with a solution 
composed of one part thirty-three degrees and three 
parts rain water 

Mortar and porous limestones react upon the solu- 
ble glass, producing carbonate of lime, hydrate of 
lime, and, ultimately, silicate of lime, which thus 
presents an impervious, vitreous surface, capable of 
resisting the action of moisture and the atmosphere, 
and is in a proper state for fresco-painting in mineral 
colors. Organic colors are apt to be destroyed by the 
alkali of the soluble glass, and hence, for fresco-paint- 
ing, mineral paints are alone available. A second coat- 
ing of paint, rubbed up with soluble glass, is usually 
sufficient for all practical purposes, and a wall thus 
treated can be washed with soap and w T ater, andkept 
thoroughly clean. A plain, white color is obtained 
by mixing chalk with soluble glass. Zinc white, and 
silicate of soda set so rapidly, that it is necessary to 
add one-quarter to one-half its weight of precipitated 
sulphate of baryta before applying the color. Baryta, 
white and soluble glass also afford a good, fast color. 
Fluor-spar, with pulverized glass and soluble glass, 
also gives an exceedingly solid mass. The pigments 
that have been found by experience to serve the best 
purpose are chromate of zinc, sulphate of cadmium, 
blue and green ultramarine, Schweinfurth green, oxide 
of chromium, cinnabar, etc. Prussian blue and colors 
prepared from it, and chromate of led, will not 
answer, as they are destroyed by the alkali, the same 
as organic colors. It is well known that the fresco- 



20 SOLUBLE GLASS. 

painting in the capitol at Washington, in the new 
museums in Berlin and Munich, are done with water- 
glass, and that the success in their use is complete. 

Soluble glass, with or without colors, adheres 
closely to such metals as iron, zinc and brass, and 
protects them from the influences of the air and 
water. It has been found that when stoves are 
painted with a mixture of soluble glass and black 
oxide of manganese, a species of flux is produced by 
the heat which does not scale off, but thoroughly 
protects the iron from any corroding action. Plate 
glass, when coated with the soluble silicate, becomes 
opaque, and when baryta is mixed with the liquid 
quartz, it assumes a fine, white appearance. If the 
glass be heated it becomes enameled, like porcelain ; • 
and fixed colors, such as ultramarine and oxide of chro- 
nium, open up an extensive application for soluble 
glass for transparencies, church windows, etc. The 
manufacture of artificial building stone by means of 
soluble glass has been conducted in Germany and 
England on an extensive scale. In Vienna, barracks 
of an enormous size have been constructed of such 
artificial stone ; and the tower of the Cathedral in that 
city was put into thorough repair in the only way 
that was possible, considering the great height of the 
tower and the extent to which it had fallen to decay. 

When ground chalk or marble is stirred into a 
paste with soluble glass, the mass becomes so hard 
that it can be employed for building purposes, or for 
the restoration of decayed stone structures. 

Marble and dolomite immersed in a solution of 



SOLUBLE GLASS. 2\ 

soluble glass, and the operation repeated a number 
of times, take up an appreciable quantity of silica, 
and become so hard that they are capable of taking 
a fine polish. Attempts to employ such stones for 
lithography have been made, but not altogether with 
success. Artificial stone can be prepared as follows : 

Well washed and gently heated sand is stirred into 
a warm solution of soluble glass until a proper con- 
sistence has been reached for pouring it into a mold. 
After it has set it is removed from the frame, which 
ought to have been previously oiled, and is left to dry 
in an airy place. To avoid too great a consumption 
of water glass, a stone or brick can be put in the 
centre of the mould. It is also possible to stir in 
pebbles and to use earthly colors in immitation of 
marble and conglomerate. Such artificial material 
becomes very hard, and is adapted to pavements, 
hearths and building purposes. 

Soluble glass can be used in the manufacture of 
paper "hangings, for printing on paper and woven 
fabrics, for attaching gold and silver powder to any 
kind of object. 

Hydraulic lime can be prepared by mixing in fine 
powder ten to twelve parts by weight of dry soluble 
glass and one hundred parts of lime — this affords a 
ready way of preparing a hydraulic cement from 
ordinary lime, which is always available. 

One of the earliest and best known uses of soluble 
glass is a cement for glass, porcelain and metals. It 
is put up in small packages for this purpose, and sold 
on the corners of streets under various names. Pieces 



22 SOLUBLE GLASS. 

of glass or porcelain cemented in this way will break 
more rapidly in pieces which were whole, than where 
they were repaired. The solution ought to be quite 
concentrated when employed for this purpose. The 
fragments to be repaired must be heated to the boil- 
ing point of water, and both surfaces be then mois- 
tened with the cement and pressed closely together, 
and held in position by a strong cord, and left to dry 
in a warm place. By mixing sulphate of magnesia 
or calcined magnesia and soluble glass, a cement can 
be formed that can be cast into moulds, and very 
generally be substituted for meerschaum. 

Wood and timber and other porous substances, 
after being boiled for several hours in soluble glass, 
then exposed in tanks containing lime water or 
chloride of calcium, and left to dry, become highly 
vitrified and incombustible. Railroad ties, ships' 
timber, house and bridge beams, have been treated 
in this manner with entire success. 

The silicate is also used for penetrating fire brick 
and clay, and for cementing the walls of furnaces. 

When stirred up with chloride of calcium and used 
for luting down the covers of crucibles, it answers an 
excellent purpose. 

i\mong the most simple processes in the silicifica- 
tion or manufacture of artificial stone is that of Mr. 
Frederick Ransome, of London, whose recent 
improvements have won for him the greatest enco- 
miums in all parts of the world, and we will here quote 
some extracts of his enlightening lecture, which he 
delivered while in this country in 1873. 



SOLUBLE GLASS. 23 

Mr. R. says that he commenced his investigations 
into the nature and properties of stone just thirty 
years since, and he found, that with comparatively 
few exceptions, the hardest and most durable 
were those in which silica abounded, either in the 
form of quartz or crystals, or in combination with 
lime or other substances. With this fact in view, he 
commenced a series of experiments, and selecting 
silicious sand (composed of crystals of nearly pure 
quartz, and which may be obtained in abundance in 
almost all parts of the world) as abase, he proceeded 
to combine the particles by the admixture of a small 
proportion of powdered glass and clay under hydraulic 
pressure, and subsequently more completely uniting 
the mass by partial fusion. After numerous unsuc- 
cessful attempts, and after having, as he believed, 
exhausted the various combination of sand, etc., with 
almost every known cement within his reach, it 
occurred to the author to substitute a concentrated 
solution of silicate of soda or potash for the other 
cementing materials he had previously employed. 
Sand, when mixed with this solution of silicate of 
soda or potash, and pressed into a mould, formed, 
when dried, a very hard stone, having a close and 
uniform texture, but which, however, became disinte- 
grated upon being exposed to moisture. The next 
step was to submit the compound to the action of 
heat, when the free alkali of the cementing silicate, 
combining with an additional quantity of the silex of 
sand, produced an insoluble silicate unaffected by 
moisture. 



24 SOLUBLE GLASS, 

In the year 1856, the author secured letters patent- 
in England, for a means of rendering stone, bricks 
and other building materials less liable to decay by 
first saturating these with a solution of silicate of 
soda, and afterwards applying a solution of chloride 
of calcium, which immediately decomposed the 
former, and produced an insoluble silicate of lime in 
the stone, etc., so operated upon ; and in the year 
1 861, in consequence of the premature decay of the 
stone of the new Houses of Parliament at Westmin- 
ster, a special committee was appointed by Govern- 
ment to examine and report on the causes of such 
decay and the best means of preserving the stone 
from further injury. The author, in common with 
others, was summoned to attend, and give evidence 
on the subject ; and after stating the satisfactory 
effects produced upon the stone of some of the 
buildings upon which he had operated, he proposed 
that, in order to demonstrate more conclusively 
the efficiency of the process, that a piece of the stone 
should be reduced to powder, and then, by the aid 
of the two solutions of silicate of soda and chloride 
of calcium, to reconvert the powder back into a 
solid stone. 

This material, in which sand and silicate of soda, 
etc., after being thoroughly incorporated in a suitable 
mixing mill and moulding into the form required, is 
saturated with a concentrated solution of chloride of 
calcium, by exhausting the air by means of air pumps, 
or by forcing the solution through the moulded mass 
by gravitation or otherwise. Double decomposition 



SOLUBLE GLASS. 2$ 

of the two solutions immediately takes place, result- 
ing in the production of an insoluble silicate of lime, 
firmly uniting and enveloping all the particles of 
which the mass is composed, and a solution of chlo- 
ride of sodium or common salt, which is subsequently 
removed by the free application of water. This 
description of stone has now been extensively used 
in England during the past twelve years, and the 
demand for it is- very rapidly increasing for all kinds 
of building materials, especially for those of an orna- 
mental or artistic character. It is perfectly free from 
all liability to distortion or shrinkage, is unaffected 
by any variations of climate or temperature, and is 
uniform and homogeneous in its texture. It has been 
most successfully employed in various countries 
abroad, especially in India, where the Government 
has established works for its manufacture. 

Its cost is less than half that of natural stone in 
details of an ornamental character, especially where 
there is much repetition, and its enduring quality is 
now so fully established as to need no comment. 

Professor Ansted states — " A parallel bar of Ran- 
some's stone, 4" x'4", resting on iron frames so as to 
bear one inch at each end, with sixteen inches clear 
between the supports, sustains a weight suspended 
from the centre of two thousand one hundred and 
twenty-two pounds. A four inch cube of Ransome's 
stone sustained a weight of thirty tons before it was 
crushed." 

One more special application in which the Ran- 
some stone has proved eminently successful may 



26 



SOLUBLE GLASS. 



suffice, viz., in the manufacture of grindstones, which 
surpass in their cutting properties all those of the 
natural stone in comparison of which they have been 
tested. 

It was found in practice that the process of washing 
the " Ransome stone" so as completely to remove 
ail trace of the chloride of sodium from large masses, 
was open to objection ; it was both tedious and 
expensive, especially in localities where there w r as a 
difficulty in obtaining a good supply of tolerably pure 
water at a reasonable cost ; besides which, in pro- 
ducing* so laree an amount, of chloride of sodium, 
which had to be afterward removed from the stone 
as a waste product at considerable cost, the bulk of 
the alkali, which was by far the most expensive 
ingredient in its composition, was ejected instead ... 
being utilized, for still further increasing the density, 
strength and hardness of the stone. 

This defect had for a considerable time engaged 
the attention of the author with the view of effecting 
a remedy, and step by step it has been accomplished 
by a process so simple and in a manner so satisfac- 
tory in its results, as to leave little or nothing to be 
desired. 

Some years since a silicious deposit was discovered 
at the base of the chalk hills in Surrey, possessing 
some very peculiar properties, amongst others, that 
of being readily soluble in a solution of caustic soda 
or potassa, at a moderately low temperature. 

Taking advantage of this peculiarity, the author 
commenced a series of experiments, in order to deter- 



SOLUBLE GLASS. 2/ 

mine if it were not possible, without the use of 
chloride of calcium, to produce a stone in all respects 
equal in quality to what had hitherto been made, and 
in this he has now succeeded, by mixing, in lieu of 
the chloride of calcium, suitable quantities of lime (or 
substances containing lime) and the natural soluble 
silica above alluded to, with sand and a solution of 
silicate of soda or potassa, which, when intimately 
incorporated, are moulded as heretofore, and allowed 
to harden gradually as silicate of lime is formed by 
the decomposition of the alkaline silicate produced 
by the action of the lime. The mass gradually 
becomes thoroughly indurated, and in a very short 
time is converted into a very compact stone, capable 
of sustaining extraordinary pressure, and increasing 
in strength and hardness with age. 

The chemical actions which produce these results 
appear to be as below stated. When the before- 
named materials are mixed together, the alkaline 
silicate is immediately decomposed, the silicic acid 
combining with a portion of the lime present, forming 
a silicate of lime, whilst a portion of the alkali in a 
caustic condition is set free ; this free alkali immedi- 
ately seizes upon the natural soluble silica which 
constitutes one of the ingredients, and thus forms a 
fresh supply of silicate of soda, or potash, as the case 
may be, which is in. its turn also decomposed by a 
fresh quantity of lime ; and so on. 

If each successive decomposition of the alkaline 
silicate resulted in setting free the whole of the 
alkali, these decomposing processes would continue 



26 SOLUBLE GLASS, 

so long as there remained any soluble silica present 
with which the alkali could combine, or until there 
ceased to be any free lime to decompose the silicate 
of soda or potash when produced ; the termination 
of the action being marked by the presence in the 
stone of the excess of caustic alkali on the one hand, 
or of alkaline silicate on the other. In reality, how- 
ever, the whole of the alkali does not appear to be 
set free as the soluble silicate is decomposed by the 
lime, there appearing to be formed a compound 
silicate of lime and soda (or potash), whereby a por- 
tion of the alkali becomes permanently fixed at each 
decomposition. The result of these several changes 
is that the whole of the alkali is gradually fixed, and 
none remains to be removed by any subsequent 
washing or other process. 

The tenacious and enduring properties of lime are 
too well known to need any elaborate explanation 
in this paper. It is the substance which has conferred 
upon the old Roman mortars and concretes 
the enormous hardness they are found to possess 
even after a lapse of two thousand years and up- 
wards. 

Upon close examination of a piece of the old 
Roman concrete, we find that the hardest part of 
such concrete is not the lime with which it was com- 
bined nor even the flint stones combined therewith, 
but the hard shelly film which has formed over the 
external surfaces of these stones, caused by the 
action of the lime with which they were in contact, 
and which is silicate of lime. 



SOLUBLE GLASS. 29 

From the foregoing remarks it will be apparent 
that, in order to produce the most satisfactory results 
in the manufactory of artificial stone of the character 
of that now under consideration, special attention 
should be paid to the selection of suitable materials, 
and great care should also be observed in details of 
manipulation. 

The silicate of soda also requires to be prepared 
with due regard to the proportions of silica and soda 
respectively, that containing sixty-six per cent, of 
silicic acid with thirty-four per cent, of soda being 
found in practice to produce the best general results. 
A sample of silicate of soda, furnished by Dr. Feucht- 
wanger, of New York, is now on the table, and 
appears to meet such conditions. 

Well-burnt Portland cement, of good quality, may 
also be advantageously employed, instead of lime of 
Teil, where now immediate setting of the mass is 
required ; but so many manufactures of the so-called 
Portland cement have of late years sprung into exist- 
ence in consequence of the increased demand for 
this article, and so much competition has been 
excited for the production of an hydraulic cement 
under this name at a low price, that more than 
ordinary care should be observed in its selection. 
The best Portland cement is composed of a mixture 
of white chalk and an alluvial deposit of rivers in a 
state of minute division, which substances, after being 
intimately incorporated mechanically, are burnt in a 
kiln to a point almost approaching vitrifaction, and 
afterwards ground and sifted, by which means a com- 



30 SOLUBLE GLASS. 

pound silicate of lime and alumina is formed, possess- 
ing the high hydraulic properties for which the Port- 
land is so famed ; but unless these ingredients be so 
mixed and burnt as to be chemically combined, 
instead of being merely mechanically incorporated, 
the so-called Portland cement may be worse than 
useless, and the employment of such material may 
lead to very disastrous results. 

In general appearance, the Ransome stone bears 
such a perfect resemblance to the natural sandstones 
as to mislead the most critical observers, whilst the 
facility of application and its economy in use will 
have been apparerjt from the foregoing description. 

It is now no difficult task to produce blocks of this 
material of any form and of any size, the only limit 
being the means available for lifting them upon the 

ot where they are to be employed. Moreover, the 
reater part of the material required for its manufac- 
ture are, as a rule, generally to be found in abund- 
vhere hydraulic or other important works are 
carried on, and for which purposes this new 
stone is eminently suited. 

According to Mr R., his artificial stone is fully 
applicable to the sculptural decoration of the exterior 
of buildings, as bas relief panels or slabs of ornaments 
of groups, and not only for enriched copings over 
doors and windows, but also for capitols of Corinthian 
columns. 

There is no efflorescence taking place as long as 
there is sufficient soluble silica and lime present in 
the materials so that the whole of the soda is com- 



- r' 



b 



he 



SOLUBLE GLASS. • J I 

bined ; for at each successive chemical action occur- 
ring during the process of formation, a portion of 
the pure soda becomes fixed and it is only necessary 
to observe carefully the correct proportion of the 
several ingredients before mixing, in order to insure 
perfect freedom from this difficulty. 

In order to produce a smooth surface on the arti- 
ficial stone, which may be liable to efflorescence 
either from the application of chloride of calcium or 
carbonates of soda or lime, the author has found that 
hydrofluoric acid possesses the most remarkable 
property to dissolve most oxides when in a concen- 
trated state. The application of the weak solution 
of hydrofluoric acid, either for fixing the potash in 
painting and in silification of limestone, was mainly 
calculated for such case where a silicate has been 
used with an excess of potash, and in hardening of 
soft and porous limestones by a partial conversion 
into a lime silicate it was found 'very expedient for 
fixing the potash and making sure the insolubility 
to moisten, at first with a weak, and then strong 
solution of the hydrofluoric acid, the stones when the 
potash oozed out ; the acid, however, penetrated the 
stone and produces an insoluble compound, in other 
words, it fixes the soluble potash, and produces an 
insoluble compound. Through this discovery hydro- 
fluoric acid was found a very useful application in the 
fluosilicated lime. 

If brought in contact with lime, hydrofluoric acid 
is capable of dissolving it considerably without pro- 
ducing an immediate precipitate of calcium, of a 



32 SOLUBLE GLASS. 

separation of the silica, but at a certain state of 
saturation any addition, of lime decomposes entirely 
the hydrofluoric acid, and so much that not a trace 
of these bodies can be discovered in the fluid.; the 
same results are obtained by the carbonate of lime, 
instead of the caustic lime, and that silicium and 
fluor are produced in the limestone, which hardens 
but slowly, and it is therefore simply a fluorsilication 
that produces the hardening of the lime. The effect 
of the hydrofluoric acid on gypsum is also produced 
in a cold mixing of both, when the surface of the 
gypsum is considerably hardened. If, however, the 
acid is used in excess, the gypsum is covered with 
raised postules, which owe their existence to the for- 
mation of bisulphate of lime, because sulphuric acid 
does not act as well as the carbonic acid in the 
treatment of limestone ; a fluorcalcium, mixed with 
soluble glass, may be used as a paint, or paste, or a 
cement, or any coating of other substances, and 
becomes so hard and waterproof that neither soda 
nor potash will detach from the combination and 
remain dry. 

Painting on Metals, Glass and Porcelain. 

Silica painting adheres strongly on metals, pro- 
vided care is taken to keep the substances some time 
from the contact with water. The most durable 
paint is produced on zinc, also on porcelain and 
glass, the colors assume a semi-transparency if 
painted on glass, and no doubt afford much induce- 



SOLUBLE GLASS. 33 

ment for its use. The sulphate of baryta, artificially 
prepared, combined with soda silicate, applied to 
glass, makes a milky white appearance, and is very 
beautiful, as it incorporates very intimately with" the 
silica, so that after the lapse of a few days the paint 
cannot be removed even with warm water. If this 
glass is exposed to high heat (six degrees Wedge- 
wood) a fine white enamel is formed on the surface, 
which will compare well with the oxyde of zinc, and 
is much cheaper. Ultramarine, oxide of chrome, if 
converted into enamels, form a prolific source for the 
new art of painting. It is not quite necessary that 
a chemical combination should be produced in all 
these colors, if they only adhere strongly and pro- 
duce the silicated cement which has become hard by 
its fine division and easy admission of air. 

Emery, bloodstone, and peroxide of manganese, if 
finely powdered and prepared with concentrated 
solution of soluble glass, produce cements of extra- 
ordinary hardness, resisting the effect of heat com- 
pletely, and become perfectly insoluble in water. 

For the production of an indestructible ink, soluble 
glass has been used and obtained by mixing finely 
burnt lampblack with the liquid soluble glass. Bra- 
connof s ink is prepared by decomposing leather in 
caustic potash and adding to the black mass the 
liquid soluble glass. A decoction of cochineal mixed 
with the liquid soluble glass produces a red ink, 
resisting completely the action of chlorine and all 
other acids. 

The alkaline salts, particularly the carbonates and 



34 SOLUBLE GLASS, 

chlorides, produce, when added to liquid silica, a 
gelatinous pasty precipitate, the chloride of am- 
monium with developing the ammonia ; precipitates 
are also formed with the earthy alkaline salts, and 
from alumina and hydrate of lime, for in all these 
cases of precipitations a part of soclais withdrawn 
from the soluble glass, which either forms a part of 
the precipitate or remains free, or attaches itself to 
the acid of the added salt. 

The same case takes place in the application of 
the salts of the heavy metals, such as iron, copper, 
etc. The effect of the soluble glass on salts, either 
insoluble or soluble with difficulty in water, such as 
sulphate of potash and carbonate of lead, phosphate 
of alumina, gypsum, etc., all of which become, when 
rubbed up with the silica solution and exposed to 
the air, a very hard mass. 

The fixation of potash with silica painting on lime 
shows how the colors, after an exposure to air for 
some time, become quite insoluble in water, and is 
thus explained : The contact of carbonate of lime 
with the soluble glass determines always the decom- 
position of the first, and conversion in silicate of 
lime, which retains the coloring matter. If the 
colors are transferred on substances not acting upon 
the soluble silicates like wood, iron, glass, etc., then 
it becomes necessary to find the conditions of the 
insolubility in the reaction of the coloring matter in 
the silicate itself. 

Much precaution has to be used not to close the 
pores of the underground, whereby the success of 



SOLUBLE GLASS. 35 

the painting is jeopardised, in case a mistake should 
have occurred before, and by waiting some time 
before proceeding farther, to allow the contraction 
of the liquid glass, so as to open again the pores, and 
which can also be accelerated by heat that is pro- 
duced by burning alcohol over the groundwork. 
Now, after this operation of drying and preparing is 
performed, and the liquid glass applied uniformly, so 
that every paint is found uniform so as to begin the 
painting, the artist will have no difficulty to begin at 
the proper work. The colors are now perfectly 
rubbed up with the water and put on artistically 
after the wall has been syringed with pure water — - 
for two reasons : one is to expel the air from the 
pores, and then to promote the adhesion of the 
colors ; this, however, must be done moderately, or 
the colors might otherwise suffer in freshness ; the 
moistening must be effected on every spot which has 
to be painted. The colors are now prepared with 
the liquid glass, diluted with one-half of its water, 
which must be applied by means of a syringe, and 
not by a brush, and with much care, for the reason 
that these colors adhere but thinly, and, if applied 
with the least force, would put the colors from their 
place, or would make them flow together ; the 
operation of syringing over, the painting must be 
repeated several times after having become dry, 
until the colors appear to be so fast, that touching 
with the fingers, they will not be stained. Many 
colors require more or less of the liquid glass, which 



36 SOLUBLE GLASS. 

may be learnt by practice, but which may easily be 
detected. 

When the painting is finished, an application of 
alcohol, after the lapse of a few days, will materially 
add to fasten the painting and to clear it from any 
impurities which may have attached themselves, or 
by the alkali which might have been separated from 
the liquid glass and have oozed out, and may be 
worked with mortar free from lime, and it may thus, 
without any hesitation, be left exposed. 

It may be observed that the painting must be 
guarded against rains during the time of the rubbing 
up and laying on of the colors. After the exposure 
of some months, or a year at latest, it is well to 
examine the painting, in order to ascertain whether 
the colors have not suffered from the condensation 
of the liquid glass, so as to produce an interruption 
of the binding or fastening of the colors, so that it 
may become necessary to apply an additional fixa- 
tion. 

The materials for the upper ground, which is to 
take up the colors, may be also composed of the 
following : Pulverized marble, dolomite, slaked lime, 
and fine quartz, or a sand with the liquid glass com- 
bined ; the proportion of the liquid glass depends 
upon the sand which is used in the mixture, so as to 
form the consistency of mortar. The advantages of 
this ground work are : It prevents the separation of 
the lime on the surface after a frequent moistening 
with water, and, therefore, no lime crust forming, no 
rubbing off is required before the application of the 



SOLUBLE GLASS. 37 

liquid glass ; furthermore, the liquid glass comes in 
immediate contact with the under ground, producing 
thereby a good cement with both grounds. This 
mortar becomes as hard as stone after being dry, and 
shows its porosity in warm and dry air, which makes 
it very susceptible for absorption. 



Stereochromic for Easel Painting. 

The basis for this class of painting may be made 
from plates of burnt, porous clay ; it is first impreg- 
nated sufficiently with liquid soda glass. These 
plates may be three-fourths of an inch thick ; after 
one or two applications they become as hard as any 
stone ware ; they are very suitable for painting 
ground. The lithographic stone makes a good base 
for easel painting ; a thin coating of liquid glass 
mortar will produce a good base, and it may be first 
moistened with phosphoric acid, which assists much 
to absorb the colors with the liquid glass and to 
make them fast. 

The colors to be used for this class of painting 
ought, not to be chosen which decomposes the liquid 
glass, such as contain strong acids, nor those from 
organic substances. Burnt oxides are better than 
raw oxides, vermillion becomes brown, and at last 
black ; cobalt blue becomes clearer by the liquid, 
and the yellow ochre becomes darker. 

All colors ought to be properly prepared to make ( 
them fit for the silica painting, such as the great 



38 SOLUBLE GLASS. 

variety of oxides, many of which, not containing 
much oxide of iron, may be suitable, also chrome red, 
ultramarine, umber, baryta white, cadmium yellow, 
and many more, purposely made by some chemists, 
not containing free acid, which enter into a decom- 
posing chemical combination. 

The permanent white, or artificial sulphate of 
baryta, is said to be the proper material for a white 
paint. It is obtained from the native minerals, 
heavy spar or sulphate of baryta, and witherite or 
carbonate of baryta or from chlor barium. The 
manufacture of the new paint is effected by the 
reduction of the native sulphate to a chloride of 
barium, or dissolving the native witherite in hydro- 
chloric acid, and then adding either sulphuric acid or 
glaubersalt, the artificial sulphate of baryta is found 
in a condition of extreme fineness and purity, 
possessing a fine lustre, and susceptible for producing 
a fine white paint, which is the best substitute for 
white lead and zinc white, is not subject to tarnish 
or become brown in parlors like white lead, which is 
attacked by hydrosulphuric acid, and forms, when 
combined with the liquid glass, a slow but intimate 
combination, and is likewise used under the name o{ 
blancfix for cardmakers, paper-stainers and paper 
collar manufacturers to a very large extent. It may 
also be considered in point of importance, if com- 
pared with that of white lead, not having a dilatory 
effect upon health as the latter. If mixed with the 
soluble glass it obviates the odious smell of linseed 
oil and spirits of turpentine. If it is mixed with 



SOLUBLE GLASS. 39 

dexterine, starch, or other binding material in con- 
nection with the liquid silicate of soda, its applica- 
tions may be multiplied to any extent. 

The artificial sulphate of baryta is largely manu- 
factured on the continent of Europe ; in the U. S. it 
has so far been manufactured in New York by a few 
chemical establishments for card makers, but not yet 
for the purpose of substituting it to white lead. 



SILIFICATION OF WOOD. 

A Protection Against Combustion, Inflamma- 
bility and Dry Rot. 

Wood, and all other organic combustible sub- 
stances, may to a great extent be preserved against 
that great element, the fire, by the proper applica- 
tion of the liquid silicates. Still it requires much 
skill, experience, and proper management to subdue 
totally this wonderful element when brought to its 
full power. There are many instances on record to 
prove either a full, or at least partial success in 
arresting the progress of a conflagration by the 
impregnation or coating of combustible bodies with 
many substances, such as possess incombustibility, 
whether liquids, gases, or materials which possess the 
properties of generating gases that will withdraw or 
suffocate the surrounding atmosphere, such as the 



40 SOLUBLE GLASS. 

oxygen gas, and thereby arrest the progress of the 
flames. Many chemical agents have been from time 
to time proposed to effect this object ; such as salt, 
chloride of lime, and latterly carbonic acid in its 
gaseous form, and many metallic salts have proved 
but a partial success in the prevention of decay or 
dry rot of wood. The soluble glass is one of the 
first materials which have been successfully employed 
in arresting conflagration, and as far as 1823, this 
material was recommended in the construction of the 
Munich Theatre, where four hundred and sixty-five 
thousand square feet of timber surface were treated 
with a coating of the liquid soluble glass, and in 
1 8 30-31 and '32 the author performed many experi- 
ments in the Brooklyn Navy Yard, partially as a 
protecting agent against fire, as also against decay 
of the woody fibre ; small square blocks of wood, 
after having been impregnated with the soluble glass, 
and sailcloth, writing paper, parchment, etc., were 
exposed for some time to the flame of a gas lamp. 
After the lapse of an hour, all these substances were 
found to be charred, but not consumed. It is proved 
that the liquid soluble glass produces a perfect 
adhering, permanent covering which, when properly 
laid on, suffers no damage from the atmosphere. 
For coating the wood, etc., a pure solution of the 
liquid glass is required, otherwise it will peel off, and 
it is best not to use it first in a concentrated state, 
as it will not be able to penetrated into the pores, 
whereby the atmosphere must be expelled, and even 
five or six applications may be made in intervals of 



SOLUBLE GLASS. 41 

twenty-four hours. Although this process renders 
good services, it may be improved by the addition of 
other pulverized substances, wherein the soluble 
glass acts as the binding material ; the coating 
assumes a better body, is stronger and more per- 
manent, and if exposed to the fire a crust is formed 
such, for instance, are bone dust, clay and chalk 
mixed together, a lead glass, etc. ; common clay 
one tenth was successfully used with the liquid glass 
in the Munich Theatre. If applied on linen or other 
organic textures, the mere coating, or dipping, is 
not sufficient, but a surface between rollers must be 
resorted to in order to produce a full absorption with 
the pores ; these stuffs may then be rolled up, but 
not folded. 

Building timber, railroad sleepers, and other 
similar materials, have been treated in the manner 
just described, and were protected fully against fire 
and dry rot. 

The author proposed a combination of the liquid 
glass with the following substances, intended as 
decomposing agents by chemical affinity, and produc- 
ing in the cells of the vegetable fibre the various 
mineral and metallic salts which are altogether 
insoluble in water, alkalies and acids, and he extended 
his experiments on the uses of lime, chalk, gypsum r 
copperas, etc. His process of treating ship timber, 
sleepers, cross-ties, roofing shingles, and other wood 
blocks was the following : 

I. The materials to be treated were put in steam- 
boilers and exposed for four hours to a pressure of 



42 SOLUBLE GLASS. 

hot steam, (or three hundred degrees F.) then with- 
drawn from the kettles and dried. Alkalies and 
acids, such as hydrochloric, have been since recom- 
mended for the purpose of abstracting color and 
albumen existing in the cells of the woody fibres y 
which, however, is accomplished by steaming. 

2. In; a solution of silicate of soda while hot, the 
materials to be treated are thrown and kept there 
for twenty-four hours, which will give ample time for 
the woods to enter into the open cells while hot. 

3. A large vat, containing either lime water, solu- 
tion of coppers, or blue vitriol, white vitriol or 
gypsum, finely powdered and thrown into hot 
water, or finely powdered chalk of one pound to ten 
gallons of w T ater ; the proportion of metallic salts is 
but one quarter of a pound, to the gallon of water. 
The woods are kept in the vats for another day, and 
then taken out dried and ready for use. 

Coal tar, and the other products of dry distillation 
from tar and peat, have been recommended by Krieg 
as far back as 1858, under the name of Kreosote- 
carbolic acid, which was then considered a waste 
product, and in its raw state having a spec. grav. 
of one hundred and two to one thousand and fifty- 
eight, and yielded from twenty to thirty per cent, of 
the tar, it was well known to possess the property 
of protecting wood against decay. 

This chemist combined with the impregnation of 
woods, etc., the soluble glass that of the creosote 
carbolic acid for the reason that the latter precipi- 
tates the soluble silica as an insoluble substance 



SOLUBLE GLASS. 43 

while it is soluble in an alkaline lye. He proposed 
to expose the woods for three-quartars of an hour to 
a temperature of three hundred degrees F., and then 
drying them thoroughly. 

The woods thus prepared showed an increased, 
weight of six percent, and a lacquered surface, while 
in the inside the pores w T ere filled with an inssoluble 
precipitated silica. 

For effecting a still more perfect success is to fix 
the creosote on the woody fibre from the alkaline 
solution, by the diluted sulphuric acid or by a solu- 
tion of copperas (sulphate of iron,) whereby the 
sulphate of soda thus obtained may either be washed 
out, or oozed out, and the creosote-carbolic acid com- 
bines stronger with the woody fibre, and the impreg- 
nated woods may be considered safely protected 
against fire or rot. 

This process just described, deserves the serious 
attention of the various companies established for 
the last five years in the preservation of wood by 
carbolic acid, tar, etc., by combining the soluble 
glass with their process, as we have described. 

Since the introduction of railroads, not quite fifty 
years, many men have been engaged in chemical 
experiments upon the cross ties and sleepers, which 
after being laid down for a few years, undergo the 
decay or rot and have to be renewed, which causes 
great expense to the companies. Kyan, Burnett, 
Boucherie and many other chemists in all countries 
where this evil existed, proposed remedies ; the 
sublimate, chloride of zinc, pyrolignite of iron, all 



44 SOLUBLE GLASS. 

had their advantages and disadvantages ; of late 
borax, alum, rosin, carbolic add have been intro- 
duced and many articles have been written on the 
subject. 

Though we have not to guard against decay, when 
timber is constantly wet in salt water, the Teredo- 
navalis, a mollusk of the family Tubicolaria (Lam.) 
soon reduces to ruin any unprotected submarine con- 
struction of common w T oods. None of our native 
timbers are exempt from these inroads. The teredo 
never perforates below the surface of the sea-bottom, 
and probably does this little injury below low-water 
mark ; its food is the borings of the wood. Poison- 
ing the timber does not protect from the teredo, 
*the constant motion of .sea-water soon diluting and 
washing away the small quantity of soluble poison 
with which the wood has been injected. Thorough 
creosoting the wood, with ten pounds of dead oil per 
cubic foot, is a complete protection against th«* 
teredo. 

Drying Timber by Steam. 

When wood is exposed to steam raised to four 
hundred and eighty-two degrees, Fahrenheit, it is 
capable of taking up a considerable quantity of 
water ; and acting upon this knowledge, we submit- 
ted different kinds of oak, elm, pine, and walnut, 
about eight inches long and half an inch square, to 
a current of steam at seven and a half pounds pres- 
sure to the square inch, but which was afterwards 



SOLUBLE GLASS. 45. 

raised to four hundred and eighty- two degrees. The 
wood w r as exposed thus for two hours. It was 
weighed before it was exposed to the steam, and 
afterward put into close-stoppered bottles until cool, 
when the samples were again weighed, and showed 
a considerable loss of weight, the loss of which 
increased with the increase of the temperature of the 
steam. For elm and oak the decrease in weight was 
one-half, ash and walnut two-fifths, and pine one- 
third. The woods underwent a change of color as 
the heat was rising from three hundred and ninety- 
five degrees to four hundred and forty-two degrees ; 
the walnut became very dark, showing a kind of tar 
formed in the wood by the process, which was found 
to have a preserving effect on the wood. 

It was found that wood thus heated became 
stronger, having an increase in the power of resisting 
fracture. The maximum heat for producing the best 
fracture-resisting power for elm was between three 
hundred and two and three hundred and forty-seven 
degrees, and between two hundred and fifty-seven 
and three hundred and three degrees for the oak, 
walnut, and pine. The oak was increased in strength 
five-ninths, walnut one-half, two-fifths for pine, and 
more than one-fifth for elm. These are but pre- 
liminary experiments, which may lead to very impor- 
tant results, and are, therefore, interesting to 
architects especially. By this process the fibres of 
the wood are drawn closer together, and maple and 
pine treated in the stream, at a temperature of- four 
hundred and eighty-seven degrees, were rendered far 



4 6 



SOLUBLE GLASS. 



more valuable for musical instruments than by any- 
other process heretofore known. This is valuable 
information to all musical instrument makers. Who 
knows but this is a discovery of the Venetian fiddle- 
makers' great secret. 

Wooden Roof Shingles. 



One of tfie most valuable applications of the soluble 
glass may be recommended for shingles and wooden 
roofs of farm-houses in the country and near railroads, 
where the sparks of the locomotives have frequently 
caused conflagrations and destruction of property. 

The operation is quite simple and the expense but 
trifling ; the process has already been described, but 
it may be still more simplified in the following 
manner : 

After the steaming of the shingles in boilers or in 
tanks, where steam of two hundred and fifty to three 
hundred and fifty degrees is led into them ; they are 
dried and thrown into a weak solution of liquid silica, 
standing about twenty-five degrees B., in which they 
are left for twenty-four hours, when they are taken 
out and exposed to the air. Before they are quite 
dry, a weak solution of chloride of calcium is thrown 
over them or sprinkled over them with a broom. 
When quite dry they are fit for use. They will not 
burn nor be ignited with the sparks ; if exposed to a 
direct fire, will not light in a surrounding fire. An 
intense heat of long duration may char them on the 



SOLUBLE GLASS. 47 

surface ; they are, however, quite safe from any 
inflamation. 

The Preservation of Wood by Immersion. 

The processes for the preservation of wood may 
be divided into three groups, namely : process by 
immersion ; process by pressure in closed vessels, 
(which are exclusively employed for dry wood,) and 
process founded on the displacement of the sap 
(which are only employed for green wood). In the 
present article we shall describe the methods by 
immersion. 

Attempts to impregnate wood by the method of 
immersion were the first experiments undertaken. 
As early as 1740, Fagol, a Frenchman, tried to 
impregnate wood with alum, sulphate of iron, and 
various other substances, in solutions of which he 
immersed it for several days. In 1756, Haller recom- 
mended vegetable oil for the same purpose. In 1767, 
Jackson indicated the use of a solution of sea salt, to 
which sulphate of iron and magnesia, alum, lime, and 
potassa were to be added. In 1779, Pallas proposed 
to mineralize wood by dipping it first in a solution of 
green copperas and afterward in milk of lime. In 
1830, Kyan in England, tried to preserve wood by 
simply immersing it in a solution containing two per 
cent, of bi-chloride of mercury. Not long since, 
experiments were made in France and Germany, 
with a number of railroad ties, by keeping them 
several hours in a solution containing one-fifth per 



4& SOLUBLE GLASS. 

cent, of sulphate of copper, at a temperature of one 
hundred and sixty degrees Fahr. This preparation 
is, however, altogether insufficient for the preserva- 
tion of fir or pine wood, and in general for light 
wools which contain a large amount of nitrogenous 
substances ; but it seems to increase considerably 
the durability of oak. The word is thus surrounded 
by a very thin coating, which is not liable to decay 
nor to the attacks of insects, and which retards the 
alteration of the inner parts. These are, however, 
not impregnated at all by the anticoptic liquid ; they 
preserve their germs of putrefaction, which develop 
the easier the more the injected surface is removed, 
whether by friction blows, or the driving in of nails. 
The decay commences then at the denuded points, 
and propagates itself toward the central parts. 

Among the bodies most prone to decomposition 
is the sugary element, which is first dissolved. Then 
the growth of fungi generally begins, and the putre- 
faction proceeds step by step. It may, therefore, be 
considered that the spontaneous decomposition of the 
vegetable albumen is the primary cause of the decay 
of wood. It is, indeed, found that those kinds of 
wood which contain the smallest quantity of albu- 
minous matter and amylum are the most durable. 
Especially is this the case with a certain tree of the 
acacia tribe, the locust, and the cedar, which resist 
decomposition in situations where all other kinds of 
wood soon decay. 

In order, then, to find out whether a certain kind 
of wood is especially fitted for building purposes, the 



SOLUBLE GLASS. 49 

quantity of albumen present in the fibre should be 
ascertained by analysis. 



Methods of Preserving Wood. 

If the primary cause of the decay of woody fibre 
be its contact with putrefying - albumen, a means of 
preserving is naturally suggested in the removal of 
the albumen ; or else in so combining it with other 
substances that it forms a compound which is insolu- 
ble in water, and not susceptible to spontaneous 
decomposition. It would seem that the solubility of 
the albumen in cold and tepid water would afford a 
simple means of withdrawing the element of decom- 
position, and thus of preserving timber ; but this 
process, though effectual, is by far too slow to be 
practicable. 

The most ancient method of guarding wood against 
decay consists in the application of an external 
coating of oils and resins, or a hot solution of silicate 
of soda, according to the author of this treatise,' in 
connection w T ith that of chloride of calcium and 
carbolic acid. If the wood is dry, and otherwise in a 
sound state, and also not exposed to abrasion, a 
perfect protection may be afforded in this way. A 
more effectual mode of preserving it, however, con- 
sists in its immersion in a hot solution of the soluble 
glass. This may either serve simply for filling the 
pores, or for forming a compound with the albumin- 
ous matters, which has the property of not being 



$0 SOLUBLE GLASS, 

decomposed. Both ends may be arrived at by one 
and the same substance. 

Timber Rot and Seasoning. 

It ris generally supposed that the rotting of timber 
is merely induced by the action of the oxygen of the 
air. From analysis made of sound and decayed oak, 
it has been shown that for every two equivalents of 
hydrogen oxidized by the air, one equivalent of car- 
bonic acid had separated. It may, therefore, be 
inferred that the decay or rot of timber does not 
arise from fermentation ; but is rather a chemical 
process. Others admit that microscopical parasities 
of vegetable nature, play an important part in the 
decay of wood ; but consider the presence of albu- 
minious matter in the sap as necessary, which, 
according to them, must also be first in a state of 
decomposition before it allows the growth of those 
organisms. In order to throw light upon this most 
important subject, we propose first to tabulate a 
number of w r ell-observed facts. Sound timber, when 
immersed in water, without access of air, will with- 
stand decay for almost an unlimited time. This is 
proved by the piles upon which the dwellings on the 
Canaries rest, which were erected in the time of the 
conquest in 1402 ; they being just as sound now as if 
they had been freshly felled. Roots of trees that 
have been submerged in marshes are rarely found 
decomposed. This is stated to be the case w r ith the 
utensils discovered in the lake dwellings of Switzer- 



SOLUBLE GLASS. , 5 1 

land, Bavaria, and Lombardy, which must be at 
least ten thousand years old. A cypress-stem with 
over three thousand rings, representing the same 
number of years, which, though submerged, had 
only partially turned into brown coal. 

With respect, to the action of the atmospheric air, 
it may be asserted that the same, even when moist, 
will not produce rot, if the wood has been well 
steamed, or exposed to the action of running water 
for a sufficient length of time. In England it is 
customary to lay the timber destined for threshing- 
floors and wainscoating in fresh water for several 
weeks. When again dry and not exposed to damp, 
such timber will endure for an. incredible period of 
time. 

This tends to demonstrate the fact that the sub- 
stance which induces decay must be foreign to the 
timber itself. This substance is the juice that is 
chiefly contained in the vascular tissue, which forms 
a link between the bark and the wood. The compo- 
sition of this sap varies according to circumstances, 
as the variety of the tree, climate, season, ground, 
etc. The following are analyses of the sap : 



i 



52 



,. SOLUBLE GLASS. 
TABLE OF ANALYSTS. 



a 3 .j 



In ioo Parts. 



>-, 



W ? 



G 



3-06(tf) 

4.37(4) 



Albumen, 

Dextrain, . 

Sugar, . 

Resin , •. . . ...... 

Galactin, . | . . . .. 30.57 

Myricin, I ..... . 

Antiarin, ........ 

Organic Substance (not determined) . | o . 1 o . . . 
Potassa with Organic Acid, . . . 

Carbonate of Lime, 

Extractive Matter and Salts, . . . 
Water, 



**5 


:r. 


-X 








C3~ 

r. 




s 




*f< 


CI 


CU 


* 


• £ 




— 


rr 






CJ 


LJ 






16 


.1 


\ 


12 


• 3 


\ 


() 


•3 


I 



0.87 

O . I o 



98.93 ! 62.00(f) 



20.93 

7.02 
3-56 



33-?o 



100.00 100,00 



(a) Gluten and Albumen, according to Solly. (t>) Dextrin and 
Salt, (c) Water and Butric Acid. 

Remarks. — The Cow Tree (Galactodron) is a native of the Cordilli- 
eras of Venzuela ; it furnishes, by incision, an enormons quantity of 
a white, thick liquid, which has the taste and some of the qualities 
of real cow's milk. The Antiaris toxicaria belongs to the same 
family as the former — namely, to the nettle-worts, and it- is singular 
that it furnishes a most deadly poison, which has been the subject of 
the most harrowing stories. (Jussieu ; Elements of Botany. 

In regard to the amount of sap and air contained 
in the oak and poplar, we possess the following data 
from Count Rumford : 

Wood. 

Oak 0.39353 

Poplar 0.24289 



Sap. 


Air. 


0.36122 


0.24525 


0.218S0 


0.53S31 



SOLUBLE GLASS. 53 

The German botanist, Schacht, in all instances of 
decayed timber, has met with fungi and lichens. 
The destruction of timber by decay, after the same 
has been hewn, must, therefore, be considered as 
being produced by similar causes which brought on 
the diseae of the vine, potato, mulbeny trees, and 
other cultivated plants, which make the years 1845, 
'48, 'S3, '57, and others forever painful to the 
memory. 

That the juice should be in a state of decomposi- 
tion before being capable of generating those organ- 
isms seems doubtful, since this has not been found 
the case in other and well-studied modes of fermen- 
tation. The morel, a species of mushroom, will also 
attack perfectly sound wood. Hand in hand with 
the spread of the fungi continues the decomposition 
of the ligneous tissue. Access to moisture and air, 
as also a certain degree of heat, are necessary. In 
regard to the air, fungi require oxygen for their 
generation. When air-dried, steamed, or chemically 
treated and afterward dried, wood commences to rot, 
it is a sign that moisture has again penetrated ; for 
it is scarcely to be admitted that in all these cases 
the sap had been entirely removed. Timber decom- 
poses the easier the more sap it contains, and if 
green trees are hewn when the vessels are overflow- 
ing with juice, one may look with certainty for 
diminished durability of the timber. Timber is not 
always the more durable the more dense it is, but 
rather when the even fineness of the gra,in continues 
to the pith of the stem. 



:r 



54 SOLUBLE GLASS, 

The Roman historian, Pliny, considers the resin- 
iferous woods as the most durable. Indeed, nature 
shows that this is frequently the case. The resin- 
iferous red and white pines of Oregon and California 
are considered first-class ship timber, so much so 
that entire vessels have been constructed from the 
denser qualities. The yellow or long-leaved pine, in 
dry situations, is extremely durable, and is preferred 
to oak of any kind where a lighter yet solid wood is 
required. The white or northern pine, which grows 
abundantly in every northern state of the union, from 
Maine to Minnesota, reaching often to an altitude of 
one hundred and eighty feet, with a diameter of six 
feet or more, is said to retain its properties as long 
as the very best description of oak. 

The fact that dried timber is, for nearly every 
purpose, far superior to green, has led to its being 
dried in the open air, or in confined rooms by means 
of heated air, or mixtures of air and steam. The 
first method is termed seasoning. Newly felled 
wood, in order that it may season properly, should 
be protected from rain, sun, and strong winds. 
It should be piled up so that a circulation of air can 
take place from beneath. 

The shed in which the timber is dried should be 
paved and provided with sewers. Moreover, the 
relative position of the pieces of timber should be 
changed from time to time during the seasoning 
process. The necessary time for seasoning varies 
from two to four years. 



SOLUBLE GLASS. 



55 



The proportion in which the woody fibre and 
water are to each other is very different. It varies 
according to the degree of dryness and the nature of 
the wood itself. According to Schubler and Neuffer, 
we have for newly felled woods the following table : 



WOOD. 



WATER. 



Hornbeam .,.,,. 18.6 per 

Willow , . , " . , 26.0 

Sycamore 27.0 

Ash . , 28.7 

Birch 30.8 

Oak . , . . 34.7 

Pedich Oak . 354 

White Fir 37.1 

Pine 39,7 

RedBeech 39.7 

Alder 41,6 



cent. 



437 



Asp , ...... 

Elm : : . 44.5 

Red Fir . . , , , 45.2 

Lime Tree 47,1 

Italian Poplar 48.2 

Larch 48.6 

White Poplar 50,6 

Black Poplar . , , 51.8 



The amount of water in wood, after one year's 
drying in the air, ranges from twenty to twenty-five 
per cent., and when perfectly air-dry, as it is oalled, 
it still holds from ten to fifteen per cent. 

The specific weight of newly felled timber ranges 
from eighty-five to one hundred and five ; that of 



56 SOLUBLE GLASS. 

air-dried timber from forty-five to seventy-five. The 
weight of one cubic foot of newly-cut native timber 
would thus range from fifty to sixty-five pounds, 
while that of seasoned wood would vary from 
twenty-eight to forty-seven pounds. The total 
expulsion of moisture by means of air-drying, accord- 
ing to the experiments of Rumford, takes place only 
at two hundred Mra eighty degrees Fahrenheit. 
But even if thus completely dried, and then exposed 
again to the atmosphere, it absorbs nearly five per 
cent, of water during the first three days, and con- 
tinues to absorb until it contains from fourteen to 
sixteen per cent., after which it becomes very hygro- 
scopic, losing or absorbing water according to the 
state of the atmosphere. 

Street Pavements. 

As a rule, competent engineers express doubts as 
to the merits of the Nicolson. and of wooden pave- 
ments of all patterns. 

In the Nicolson structure the road-bed is of sharp, 
clean sand, of the proper thickness. A basis is 
made by laying common boards, dipped in hot coal- 
tar, lengthwise on stringers of like material laid from 
curb to curb. The blocks forming the superstructure 
are of southern hard pine, three by four, and are set 
on end in rows, crosswise of the street — the blocks 
before setting being dipped to half their length in a 
bath of coal-tar. Between the rows of blocks inter- 



SOLUBLE GLASS. 57 

vene pickets of thin board set on edge and leaving 
an opening between the rows of blocks, of a foot or 
nearly in depth. This opening is filled with clean, 
screened gravel, rammed down with a paver's 
hammer, and an iron blade made for the purpose, 
and the surface is covered with hot coal-tar. The 
gutter exhibits its lowest point half a foot from the 
curb. The whole surface is covered with coal-tar 
sufficiently boiled to be tough and fibrous, but not 
brittle, upon which is sprinkled a layer of fine gravel 
and common sand. 

Most foreigners travelling in France, remark the 
excellence of the macadamized roads, and not unfre- 
quently suppose that there must be something 
peculiarly favorable in the nature of the soil or some- 
thing unique in the method of construction. The 
supposition is not true to fact, however ; the quality 
of the roads in France being attributable to good 
engineering and care, and exactness in all the process- 
ess of construction and preservation. In fact, in the 
system of Telford and Simplon the system intro- 
duced in England by MacAdam, in 1816, had been 
anticipated more than half a century. MacAdam 
copied Simplon in his road-bed, while Tilford did 
nothing more than return to the system founded by 
Tresaquet in place of the still earlier road-bed of 
flat stones. The roads of France are simply illustra- 
tions of what may be done by good construction 
rather than of any superiority of facilities ; those of 
the city of New York are to a great extent examples 
of the result of slovenly construction with sufficient 



58 SOLUBLE GLASS. 

facilities for the best of work. And this leads to the 
general principle, that of the several pavements in 
use any one is practically good enough for all pur- 
poses when well constructed. The defect is not in 
the theory of the pavement itself, but in the defective 
and slovenly application of it under the contract 
system. As in railroad building, with the result of 
innumerable accidents, so in street paving defective 
road-bed is the great sin of the contractor ; and, as 
in railroad building, the United States cannot be 
compared with France or England for thoroughness 
and attention to the details which result in perfec- 
tion, so, in the matter of pavement and the laying of 
it, American contractors on the average are slovenly 
and inefficient. Contracts for street paving are 
annually awarded in this city to persons whom a 
competent European engineer would not trust as 
workers under a superintendent ; and thus, through 
ignorance in many cases, through greed in many 
cases, and through both together existing in many 
cases, it is seldom that New York can boast of a 
ection of pavement properly put down with due 
attention to all details. 

The following method of application is recommen- 
ded by the author : 

The planks and wooden blocks, intended as pave- 
ment, the size of the planks being from ten to twelve 
feet in length and one inch in thickness, and the 
blocks from ten to twelve inches square ; and in the 
first place exposed in iron boilers to a temperature 
of three hundred degrees F. for several hours, or kept 



SOLUBLE GLASS. 59 

for four to six hours in boiling water, containing two' 
per cent, of soda ash, which possesses the property 
of dissolving the albumen and sap contained in the 
cells of the wood, and, by the boiling, the coloring 
matter is extracted from the wood. When taken 
from the boilers, they are brought in drying cham- 
bers of high temperature, and then removed to vats 
containing crude carbolic acid and tar water stand- 
ing from six to eight degrees B., which will enter into 
the pores left open by the previous process and a 
large portion of the liquid will be absorbed ; from 
thence they are thrown into vats containing hot silicate 
of soda, standing twenty degrees B. and left therein 
for four to six hours ; they are then removed and 
dried either in air or hot chambers. When perfectly 
dry they are suitable for being put on a smooth 
ground, which may consist of a cement of silicated 
hydraulic lime or cement. The interstices of the 
ends of the blocks may likewise be made tight by 
applying a silica cement between each. 

The frequent enquiries, how to apply the soluble 
glass, and how much is required for spreading over 
certain surfaces, may herewith be recommended in 
the following manner : application for hardening 
stones as a mortar between bricks, or any cement or 
composition for wall, cistern, cellar, or roofing. 

In all cases the liquid soluble glass, either the 
silicate of soda or potash, or both combined, are 
diluted with equal quantities of water so as to stand 
twenty-five degrees B. If strong cements, or lutes, 
where various other substances along with the dry 



60 SOLUBLE GLASS. 

silicate and metallic oxides are to be employed, the 
soluble glass is not diluted but, employed from thirty 
to thirty-five degrees B., sufficently to make a plastic 
composition. But where it is intended for mending 
or filling cracks or holes, either in stoves or iron 
castings, discretion of the consistency of the mass 
must be used, as it may be more advantageous for 
the cement to dry slowly, so as to prevent too 
sudden a contraction. 

For painting or coating on stone, it is useful to 
apply the dilute by a syringe, and if necessary, repeat 
the operation two or three times after each drying. 
For preserving monuments, tombstones, marble 
columns, etc., the dilute silicate of soda may be used 
as a wash with or without the addition of baryta (the 
precipitated sulphate of baryta is always preferred 
although expensive), lead, zinc, or lime w T ash, by 
means of a paint brush and according to the condi- 
tion of the stone as to porosity. If the chloride of 
calcium, chloride of iron, or dilute hydrofluoric acid 
are applied upon the surface of the stone, cement or 
paint, they are thrown over the silicated surface 
uniformly, so as to cover every part of the material 
to be treated. In all cases it is understood that the 
silicate application is to be applied on new stone, for 
it will not adhere on old paint ; therefore, if it is to 
be used, it is indispensable that it be first removed by 
soap, caustic alkali, spirits of turpentine, or even 
acids, and when perfectly clean and dry, the opera- 
tion of silicating may take place. In all cases where 
the substances are to be painted or undergo a silifi- 



SOLUBLE GLASS. 6l 

cation, it may be repeated two or three times at each 
interval of at least twelve hours ; a weak hydro- 
fluoric acid may in all cases be used as a wash over 
the silicated stones. One thousand square feet of 
wall covering can be executed with two hundred 
gallons of dilute silicate of eithersoda or potash. In 
diluting the silicate, it is well to employ three appli- 
cations of various qualities such as, for instance, 
the first coat may consist of part of silica to two parts 
of water, and another of equal quantities of water, 
and the last coat the dilution to be one part of 
water. 

Wood and timber of every description may be 
treated with the concentrated silicates. 



ON MORTAR AND CEMENTS. 

" The earliest architectural constructions to fasten 
together the bricks or stones of which buildings are 
made were of various kinds ; the most common is 
called mortar. It is obtained by first calcining crude 
limestone in a kiln, and^converting it into quicklime, 
by depriving it of its carbonic acid. After calcining, 
the resulting quicklime is of a whitish or grayish pow- 
dery and cracked substance, which, on the application 
of water, absorbs a certain quantity with the evolution 
of much heat, and crumbles into a fine powder. This 
powder further moistened, made into a thin paste 
with water, and mixed with two or three times its own 



62 SOLUBLE GLASS. 

weight of sharp sand, is called mortar. Slaked lime, 
or hydrate of lime, as moistened quicklime is called, 
absorbs carbonic acid from the air, and in time mor- 
tar is reconverted into limestone ; but the operation 
goes on under peculiar conditions, and the result is 
also peculiar ; for a film of silicate of lime is formed 
round each grain of sand, and thus the whole mass 
and the stones, between which it is placed, become 
in time more compact than the particles of lime- 
stone. 

" As, however, there are different kinds of limestone 
more or less impure, the result will be limes of very 
different qualities and properties. These require 
special treatment to obtain from them the best results. 
The purest carbonate of lime, such as marble, or 
chalk, make what is called a rich lime, setting firmly 
only in dry air, while the very impure carbonates, in 
which clay is largely mixed with the limestone, 
result in the production of hydraulic limes, which set 
more or less rapidly in moist air or even under water. 
Some of the impure limestones are used in the 
manufacture of cements by the admixture of definite 
proportions of foreign ingredients. Sometimes, by 
the admixture of a certain substance (as puzzuolana) 
with the rich limes, instead of sand, hydraulic limes 
are produced. There are few subjects connected 
with the application of geology that are more impor- 
tant, than the determination of the material that 
should be used and the treatment adopted in various 
countries in the manufacture of cements, mortars and 
stuccos. 



SOLUBLE GLASS. 63 

" Commencing with nearly pure carbonates of lime, 
it is not difficult to trace the changes that take place 
in their convertion into cements. A layer of such 
mortar, not too thick, placed between bricks or 
stone, w r hich are themselves absorbent, and kept in 
dry air, dries gradually and holds together such sub- 
stances with extraordinary tenacity. But this is a 
work of years, and sometimes even centuries must 
run out before the extreme of hardness is attained ! 
It is not unusual to find imperfectly hardened mortars 
in very old constructions. The mortar that fastened 
together the bricks in the old Roman walls is now 
almost eveiywhere so far hardened that a fracture 
takes place in the brick rather than in the cement. 

" Limestone is widely distributed, and almost every 
variety, however impure, can be burnt into lime. In 
the manufacture of good common mortar to set 
in the air, pure limestones and those of fair ordinary 
quality are available ; but in using them, attention 
must be given to their composition and even 
texture ; thus, the hardest limestones and marbles 
make the fattest lime, but each variety yields a lime 
of different quality, distinct in color, in weight, in 
the greediness with which it absorbs water, and in its 
ultimate hardness. The method of calcination also 
varies, but the general result is that, after burning the 
limestone, the resulting quicklime is lighter than the 
original stone, and differs from it essentially. 

The word hydraulic, as applied to lime, means 
only that it possesses the property of setting, or 
becoming solid, in moist air or under water. 



SOLUBLE GLASS. 

" Rich limes are obtained from the purest and 
hardest limestones. When slaked, they increase to 
double their volume ; if employed alone, they remain 
unaltered even for years, and they are soluble in 
pure water. Limestones which contain from one to 
six per cent, of foreign substances, such as silica, 
alumina, magnesia, etc., yield rich limes ; but such 
as contain from fifteen to thirty per cent., are poor 
limes ; they increase in bulk, but little on slaking, 
do not set under water, and are soluble, like the rich 
limes, xecept that they leave a residuum. The fosili- 
ferous limestones make bad mortar, as the slaking is 
irregular ; limestones containing much silica swell in 
setting, and may dislocate the masonry executed 
with them. Where alumina is in excess, the lime is 
apt to shrink and crack. Where carbonate of mag- 
nesia is combined with carbonate of lime, as in the 
magnesian limestones, the original bulk is retained. 
For ordinary purposes, moderately pure limestones, 
with a mixture of foreign substances, is a moderately 
pure limestone. Hydraulic limes are of great value 
in construction, and are extremely interesting, and 
are either obtained naturally from the burning of 
certain varieties of calcareous rock, or are manufac- 
tured artificially by mixing limestones with the 
requisite foreign ingredients ; such are the Roman 
cement, Portland cement, Parker's and Rosendale 
cements. The Portland cement is largely manufac- 
tured at the mouth of the Thames, from a mixed 
river mud, while Roman cement is formed from the 
nodules found in the cliffs near Harwich, all owing 



SOLUBLE GLASS. 65 

their quality to argillaceous admixture. Limestone, 
containing from fifteen to twenty-five per cent, of a 
silicate of alumina, will burn into a good hydraulic 
lime. It is also quite certain that the oxide of iron 
and carbonate of magnesia exercise a great influence 
in rendering limes more hydraulic. All materials 
intended for the manufacture of cements require to 
be burnt carefully, and ground down to a fine pow- 
der, and the best cement is the lightest. When 
these cements are intended for the production of an 
artificial stone, from ten to twelve times the weight 
of broken pebbles are added, and form also an excel- 
lent concrete. A stone made from these cements 
just described, will bear a strain varying from twenty 
to sixty pounds to the square inch. 

" The plaster cement is obtained from the gypsum, 
or sulphate of lime, abundant in England, France, 
and the United States ; is treated like common lime- 
stone for a cement. The calcining of gypsum does 
not involve its decomposition, but the water of 
solidification being driven off by the calcination, 
leaves only a soft white powder called 'plaster of 
Paris ; when this is again united with water, the 
latter is absorbed, and the mass becomes first, 
plastic, and then solid ; but it cannot be brought 
back to its original condition as a crystalline mineral, 
but it is converted into various substances used as a 
cement, such as Keene s cement, if alum is added to 
the fine powdered plaster ; parian cement, if borax 
is used ; Martin's cement, if pearl ashes are employed. 
Stucco is a very useful material for ornaments for in 



65 SOLUBLE GLASS. 

and out-door work, is nothing else but a plaster of 
Paris, finely ground, and a weak glue added before 
mixing it with water. 

44 One of the richest kinds of hydraulic lime may 
be obtained from volcanic minerals mixed with 
limes ; such material is the Puzzuolana, found near 
Naples, as well as other substances found in large 
quantities in the neighborhood of extinct volcanic 
districts, as in France and on the Rhine ; and which, 
according to its chemical analysis, consists of forty- 
four per cent, of silica, fifteen per cent, alumina, 
eighty-seven per cent, lime, four per cent, magnesia, 
and twelve per cent, oxide of iron ; combined with 
lime instead of sand, have the property of rendering 
even the richest limes hydraulic, and fit for use for 
every description of works executed in the sea or in 
the fresh water ; they have been used from time 
immemorial with great success, and may be mixed 
either with fat or hydraulic limes and silicate of soda 
to form a plastic mass, and assist in the setting of 
the lime. 

41 In many cases the chemical composition of an 
argillaceous limestone is not only the condition 
which determines the quality of the cement ; the 
reaction of the lime upon the clay must take place at 
the highest temperature. Indeed, this excessive 
heat produces the hydraulic elements of the cement 
in the basic conditions which the setting in the water 
requires, and which, by melting the aluminate of 
lime, gives it all its activity. 

4i The Roman or hydraulic cement mostly contains, 



SOLUBLE GLASS. 



6 7 



also, magnesia and iron ; whether of any essential 
benefit or not, has not been fairly tested. It is cer- 
tain that neither of these substances exercise a per- 
nicious influence, for the reason that dolomite, a 
magnesian limestone found in great abundance in 
this country, offers a fine mineral when calcined with 
any marls, so abundant along our coast. It produces 
an excellent hydraulic cement. 

" The analysis of the hydraulic lime from Rondout, 
on the North River, gives in one hundred parts : 



Carbolic acid ...... 35 

Magnesia . . . . . . .12 

Alumina ....... 10 



Lime ....'.... 26 

Silica . 15 

Iron . 2 



" Sand or quartz, which by itself is unfit for a mor- 
tar, when calcined with lime, becomes very suitable 
for a hydraulic cement or artificial stone, for it forms 
a silicate of lime. More than thirty vears ago, I 
entertained the idea of preserving timber by the 
infiltration of silicate of lime into the cells of planks, 
timber, and through the double chemical affinity of 
silicate of soda and sulphate of lime. The experi- 
ments I made then, in the Brooklyn Navy Yard, 
with pier piles and wooden vats, were very satisfac- 
tory. 

" For water-proofing cellars and buildings, not 
alone the best hydraulic, but other cements have of 
late years been introduced in this city ; for instance, 
the asphalt cement, which is very extensively em- 
ployed in the foundation of buildings. Having made, 
myself, many experiments, for a number of years 



68 v i SOLUBLE GLASS. 



past, in order to introduce the silica cement, or the 
soluable glass, in combination with alkaline earths as 
a base, and met with varied success, I beg to offer 
here a sample of a cement which consists of silicate 
of lime combined with manganese and fluorspar, or 
fluoride of calcium, which becomes very hard, and 
which, I think, will, after some improvement in the 
preparation, be found highly useful in keeping dry 
walls and cellars. I have mixed equal quantities. of 
manganese, limestone, fluorspar, and dry soluble 
glass, and make the whole mass plastic by the liquid 
soluble glass, and apply it while soft ; after the lapse 
of a few hours it becomes very hard. 

" Among the great variety of cements in which 
silica is the active principle, the two following are 
very useful : 

M I. A mortar, to be made as hard as any cement, 
and which does not crack in setting, and even of 
great usefulness as hydraulic cement under water, is 
obtained by mixing finely slaked lime with fine sand 
(the angular grains are always preferable to the 
round grains for producing a good mortar,) — by 
mixing the sand thus prepared with finely powdered 
quicklime, and stir the mixture thoroughly. During 
the process the mass heats, and may then be em- 
ployed as a mortar, to which has to be added to 
one-eighth of the mass, the liquid silicate of soda. 

"One part of good slaked lime was used with 
three parts of sand, and to this was added three- 
fourths of its weight of finely powdered quicklime ; 
the mortar containing one-eighth of the liquid 



SOLUBLE GLASS. 69 

silicate of soda was then used as a foundation wall, 
and in four days had become so hard that a piece of 
sharp iron would not attack it ; and in two months 
afterwards it had become as hard as the stones of the 
wall. 

M 2. A thin coating of slaked lime made into paste 
with water or whitewash is put at once on the stone, 
and before becoming quite dry apply the silicate 
solution over the paste, by which means the mass 
becomes completely insoluble ; a petrification takes 
place if applied to vegetable substances, decomposi- 
tion is prevented, porous building stone and brick 
are protected against air and clamp. 

44 Common Mortar. 

44 Limestone, an impure carbonate of lime, when 
exposed to a red heat, loses carbonic acid gas, and 
the oxide of calcium or lime remains. This process 
of burning lime, as it is called, is accelerated by the 
presence of moisture in the stone, or by the introduc- 
tion of a small quantity of steam into the lime kiln. 
The hydrate of lime reacts with considerable .power 
on siliceous compounds, but the action only takes 
place at the surfaces, and unless the lime is used in 
very thin layers, between smooth stones, it still 
retains, in the centre of the layer, its own soft and 
friable condition. 

44 In order to make the hydrate of lime effective as 
a cement, it is mixed with sand, one of the most 
abundant of natural compounds, now regarded as 



70 VJ SOLUBLE GLASS. 

consisting of two atoms of oxygen and one of silicon. 
Equal parts of fine and course sand are said to be 
better than either quality used separately with lime. 
Mortar designed for exterior or surface work is 
generally made with fine sand. When lime is com- 
paratively free from impurities, and crumbles to a 
fine powder on being slaked, it is called fat lime, and 
well require about six times its own weight of sand, 
or, if estimated by bulk, one cubic foot of s^mi-fluid 
lime and water, called the milk of lime, will require 
about three or four cubic feet of sand. This mortar 
is very effective as a cement when well dried or set, 
but if it is placed in water, the lime is gradually dis- 
solved and the mass is disintegrated. 

" Hydraulic Cement. 

" For all permanent structures under water it is, 
therefore, essential to use a material called hydraulic 
cement, which is a mixture of lime with other oxides 
possessing the valuable quality of hardening until it 
has the solidity and permanency of the masses of 
rock bound together by it. The varieties of lime- 
stone from which hydraulic cement is made, when 
burned, yield a lime that is very slowly slaked. All 
that is required is to add wa'ter until it attains the 
consistency of dough ; it will then harden and 
become concrete. These hydraulic limes may be 
made artificially by mixing with impure slaked lime 
a quantity of burnt clay in the proper proportions. 
The celebrated Roman cement is a porous volcanic 



SOLUBLE GLASS. J I 

rock found at Puzzuoli, near Naples, and called 
there puzzuolana. It consists of silicate of alumina, 
soda and lime. This substance is pulverized and 
mixed with common lime." 

The Silicate Hydraulic Cement in the Pre- 
vention of Wall-Damp. 

In laying the foundation of any building, the mat- 
ter of particular consideration should be the thorough 
drainage of the site, and next to that complete pre- 
vention of wall-damp, that is, the rising of moisture 
by capillary attraction or otherwise, in the heart of 
the brick or stone work. Wherever brickwork comes 
in contact with the earth, or even with the adjacent 
walls which may happen to be damp, there the infec- 
tion is certain to take, and there is no easy cure for 
it, if once it makes an entrance. 

The readiest remedy in all cases is a layer of fine 
concrete, which may be thinly coated on the top 
with asphaltum laid on hot. This done all around 
the top of the walls, external, the piers and every 
piece of brickwork, that in any manner has connec- 
tion with the ground, then the bricks, which ought 
to be specially prepared before calcination with a 
silicate solution, should be heated over charcoal 
furnaces and dipped in the asphaltum before being 
laid. It is evident that a preventive course could 
thus be formed above ground at a trifling expense, 
wholly impervious to wall-darnp, at the same time 
giving a base to the superstructure of a quality very far 



72 SOLUBLE GLASS. 

superior to any now in use. Coating the outside 
face of the wall with water-proof silicated cement, as 
has been before noticed, is the only safeguard against 
capillary attraction from below, and excluding the 
external air which might let the artificial heat of the 
rooms to attract the enemy of wall-damp. It is known 
that common brick will absorb one-fifth of its weight 
of water, and where the storm drives the rain con- 
tinually against the face of a wall for a sufficient 
time to permit the interior heat to attract it, the 
inside of the wall must, of necessity, be damp, and 
the papering become mouldy, as well as the ceiling, 
will next be rotten. This cause of wall-damp is one 
that cannot be too carefully guarded against, as it is 
one to which may be referred the early decay of 
many residences, as well as the inception of these 
pulmonary symptoms which so surely steal away the 
health and ultimately the life of many a victim. 

The mortar to be used in the foundation and the 
wall ought to be very well prepared, so as to possess 
all the hydraulic properties and silicification, and 
caution should be taken in not using sea sand, which 
will certainly create the damp by absorbing all the 
water in the atmosphere, this being the chemical 
effect of its saline property. 

The surface of the walls of the rooms must be well 
attended to ; the plaster of Paris, which is generally 
employed, ought to be properly silicified, so as to 
prevent the absorption of the natural damp of the 
atmosphere created in uninhabited and unheated 
rooms. 



SOLUBLE GLASS. 73 

It is preferable to paint rooms than to paper them, 
for the white lead and linseed oil, with some man- 
ganese to facilitate the drying, becomes hard alter a 
short time, and assists the fresh plaster wall in pre- 
venting the admission of the moisture, as the fourth 
coating of white lead is applied with equal portions 
oil and spirits of turpentine, which has the property 
of being very volatile, will evaporate entirely, leaving 
the surface of the paint of a very compact and hard 
nature, and rendering the plaster incapable of absorp- 
tion. 

Damp Walls and Cellars. 

The application of silicates for preventing the 
penetration of rain or moisture in houses, whereby 
the walls are absorbing the same, and render the 
paper-hangings or delicate paint unfit, so as to 
destroy their appearance, has been amply and satis- 
factorily proven. The silicates of soda and potash, 
or either of them, are mixed with pure white lead 
or zinc, and applied soon after upon the walls, which 
will dry immediately. 

The presence of damp in walls arises from three 
causes : either from the porous condition of the 
materials of which they are built, allowing the pene- 
tration of damp from without ; from the existence of 
salts in the mortar, bricks or stone, which absorb and 
give out moisture, according to the changes of the 
weather, or from damp foundations. The first only 
c an be remedied by the application of external coat- 



74 SOLUBLE GLASS. 

ings, the second by battening the walls, and the last 
by removing the adjacent earth from the founda- 
tions. 

As has already been stated, a single application of 
a paint formed with lead or zinc has proved very suc- 
cessful. The second application is the silicate 
solution with china clay, or pure alumina, which has 
the advantage of not drying so quick as that with 
lead or zinc. In all cases the paints must be put on 
uniformly, so that the whole wall surface should be 
completely covered with the solid coat ; and in order 
to effect this, a rough stucco surface, from two to 
three coats may be required. It is found also useful 
to apply the second coat thinner than the first. 

The mixture of liquid silicate of soda with clay and 
that of whiting, or washed carbonate of lime, may 
probably be the most reliable for keeping out damp 
from walls as well as cellars. 

On applying the lead or zinc as the first coat, 
either of them or both, it may be done in the follow- 
ing manner : 

Mix them with a little water and lay them on the 
stone ; they will dry very soon ; apply then the 
silicate solution by means of a syringe. If the appli- 
cation is to be made on stone which shows some 
decay, it is necessary to remove first the same ; 
apply then the aluminous silicate of soda (by an 
equal mixture of liquid silicate with fine white clay), 
and then apply the carbonate lime and silicate wash 
with an ordinary paint brush, stipping it so as to give 
it the appearance of the granulated surface of the 



SOLUBLE GLASS. 75 

stone. When dry, it will adhere sufficiently to allow 
of other washes of silicates being brushed on it. 
The conditions necessary for success are : 

1. The wall should be coated with a porous mate- 
rial, such as lime or Portland cement. . 

2. The coating must be perfect. A wall which 
has been once painted is altogether unfit for any 
application of siliceous washes, for the reason that it 
is not absorbent enough. 

The best ground for any siliceous work is lime and 
sand. In new buildings it would be better to use 
lime and sand at once, and then to cover it with 
lime and silicate of alumina and soda. The precipi- 
tated sulphate of baryta may safely be applied in the 
silicate of soda for all the above purposes, and it will 
produce a good coating and a fine paint. 

Manufacture of Portland Cement. 

Portland cement was introduced to public notice 
under a patent by an Englishman, nearly fifty years 
ago, and a partial monopoly in its production has 
been kept up, inasmuch as inexhaustible beds of the 
raw material from which it is made, and an abundant 
supply of fuel necessary for their economical manu- 
facture, is at hand. It is strange that under these 
conditions French engineers should have obtained 
the start of their professional confra'es^ and that they 
should have been the first to demonstrate by experi- 
ments, and subsequently by the erection of magnifi- 
cent harbor works on their seaboard, the valuable 



76 SOLUBLE GLASS. 

properties of this excellent constructive material. 
We may date the extensive employment of Portland 
cement in England from the commencement of the 
metropolitan main-drainage works. During the last 
fifteen years the manufacture of Portland cement has 
gone on steadily increasing, until at the present day 
we find that little short of five hundred thousand 
tons per annum are made in the county of Kent — 
the centre of cement manufacture — irrespective of 
the productions of many minor factories in different 
parts of the country. 

The chemistry of the setting of Portland cement 
is by no means so well understood as it ought to be. 
There is no doubt, however, that, like the hydraulic 
lime and natural cements, it is, chemically speaking, 
a double silicate of lime and alumina ; silicic acid is 
generated by the hydration of the cement, and forms 
insoluble salts with the lime and alumina bases. It 
is a curious fact that Portland cement hardens more 
rapidly when salt water is employed. According to 
Schweitzer, one thousand grains of sea water in the 
English Channel contains twenty-seven thousand 
and sixty grains of chloride of sodium ; soluble silica 
has a known preference for alkaline bases, and it is 
not improbable, when the cement is hydrated with 
sea water, that the chloride of sodium is decomposed, 
the silicic acid of the cement combining with the 
sodium and oxygen of the water, and forming thereby 
a silicate of soda, or a species of crude glass. 

Portland cement is of two classes, which, for the 
sake of distinction, may be termed " Engineers' " 



SOLUBLE GLASS. JJ 

cement and " Plasterers' " cement. The former is 
the more costly ; it is usually described by manufac- 
turers as " best heavy tested ;" it weighs from one 
hundred and twelve pounds to one hundred and 
tw T enty pounds to the bushel, is slow setting, and of 
great strength ; the latter is a light cement, quick 
setting, and of inferior strength when compared with 
the other. It must be understood that our remarks 
apply exclusively to " Engineers' " cement, 

Portland cement is made from chalk and alluvial 
clay ; the factories on the banks of the Thames use 
white chalk, those on the Medway gray chalk ; the 
latter is probably preferable, inasmuch as it contains 
large quantities of siliceous matter. Mr. Read, in his 
treatise on " Portland Cement," says that " the pre- 
sent and safest proportions, provided both chalk and 
clay are selected free from sand, are four parts of 
chalk from the Medway (gray), or three parts of 
Thames (white), with one of clay by measure." 
These materials are placed in mills of simple con- 
struction, each having a circular pan, six feet in 
diameter and two feet deep, in which two " edge 
runners," four feet and six inches in diameter, are 
kept continually going ; a constant stream of water 
flows into the pan, and as the "edge runners" 
revolve, the chalk and clay are thoroughly 5 ground, 
. and, being thus converted into a fluid state, they 
filter, through a band of fine brass wire ,gauze fixed 
to the side of the pan, and flow through wooden 
" launders " into tanks or settling reservoirs. One 
wash-mill will feed four tanks, each of which is about 



y8 SOLUBLE GLASS. 

one hundred feet long, forty feet broad, and four feet 
deep. When one of these has been filled in the 
manner just described, the same process is applied to 
the others in succession. About three weeks after 
the tanks are filled, the whole of the materials will 
be precipitated, the clear water being drained off in 
the meantime through a small weir in the brick side 
of the tank ; the residuum is a plastic mixture of the 
consistency of " putty," and not much unlike it in 
color. The next process is to convey this precipi- 
tate from the tank to the 4t drying floors," over which 
it is spread in a layer about six inches thick ; each 
floor is forty feet by thirty feet ; it consists of an 
outer skin of boiler plates, sufficiently hot to effect 
the rapid desiccation of the water from the superin- 
cumbent layer, a process generally accomplished in 
about twelve hours. The materials having thus 
been thoroughly dried, are ready for conveyance to 
the kilns. The " charge " consists of alternate layers 
of coke and raw materials, the burning generally 
occupying thirty-six hours. When tiie contents of 
the kiln become sufficiently cool, the " clinkers," or 
cement stones — for the mixture has now assumed 
that form — are drawn and removed to a floor where 
the larger pieces are broken, and the whole of the 
burnt materials are then conveyed to the hoppers of 
the grinding mills, where, passing under rapidly 
revolving horizontal burrstones, they are ground 
into an almost impalpable powder. The cement 
issues from the mill at a temperature of about one 
hundred and sixty degrees, and the now manufac- 



SOLUBLE GLASS. 79 

tured material is wheeled away, and placed in a layer 
from two feet to three feet thick over the floor of a 
cool shed ; it is subsequently packed in casks or 
sacks for conveyance from the works. The essential 
conditions for the manufacture of good Portland 
cement are: I. The chalk and clay should be 
thoroughly mixed in the wash-mills, and the fluid 
materials delivered by 6l launders " over the entire 
area of the settling tanks. 2. The contents of the 
kilns ought to be burnt equally throughout. 3. The 
burnt materials should be ground very fine. 4. 
After coming from the mill the cement should be 
spread over the floor of a shed, and allowed to 
remain there for at least a fortnight previously to 
being packed in casks or sacks. 

The strength of Portland cement increases as its 
specific gravity increases ; the tensile tests are 
usually made with briquetts, the standard size for 
the neck being one and one-half inches by one and 
one-half inches ; and it must be understood that all 
experiments referred to have reference to the weight 
necessary to sever two and one-quarter square inches 
of neat cement. 

Portland cement now forms an important item in 
the list of our manufactures ; but even now its 
valuable properties are not as fully appreciated as 
they deserve to be. It should present a fine and 
homogeneous powder ; it should set firmly and 
quickly, when used in works exposed to the surf, 
filling up joints in water works, etc., otherwise too 
rapid setting is not desirable. It should neither con- 



So SOLUBLE GLASS. 

tract nor expand ; it ought to assume a uniform, 
bright, gray-stone color, free from brown spots ; it 
should possess great cementing properties, adhere 
strongly to the stone, and bear a high addition of 
sand. Finally, it ought to be free from adultera- 
tions, while the ton should have the generally 
adopted weight of two hundred kilogrammes. It is 
to be recommended, under all circumstances, and 
even if the cement has been procured from well- 
known manufacturers, to weigh it on delivery, and 
to keep an accurate account of it. It is very often 
the case that the weight is considerably below two 
hundred kilogrammes, due either to the frequent use 
of the same barrel, which almost inevitably gets 
smaller, or to bad packing, which produces incom- 
pactness ; or to unpacking it in smaller barrels, 
which is often done by second or third hand dealers. 

A difference of ten or twenty kilogrammes per 
ton, which often occurs away from the centres of 
trade, ought certainly to be taken into considera- 
tion, if occurring in larger quantities. 

In order to examine cements for their fineness 
and uniformity of mixture, it is only necessary to 
pass samples or different barrels through sieves of 
twenty meshes per centimetre. 

There should, properly speaking, remain nothing 
on the sieve, and under all circumstances, preference 
must be given to the cement which most nearly ful- 
fills these conditions ; for the finer and more 
uniformly the cement is divided, the more promptly 
and simultaneously will the chemical reactions take 



SOLUBLE GLASS. 8 1 

place, the more perfect its combining and cementing 
properties, and the less fear is to be entertained 
about a. durability of the mass after it has once prop- 
erly set. The most common adulterations are 
inferior or spoiled cement, slags, ashes, clay and 
sand. They are most easily discovered by constant 
shaking of a sample with an abundant amount of 
water, after which it is allowed to settle in a high, 
narrow vessel. The cement to be examined is to be 
put in the glass filled two-thirds full of water, after 
which it must be shaken at once, or the cement will 
cake together and stick to the vessel. Ashes and 
clay deposit on top, on account of their smaller 
specific gravity, and the water in this case generally 
looks turbid. The upper portion of the sediment 
generally fails then to harden at all, but exhibits a 
distinctly different color from the rest of the mass. 
A close examination of it will then usually disclose 
the nature of the adulteration. 

When made into paste, with sufficient water to 
produce a mortar which slides smoothly from the 
trowel, pure cement should not set in less than 
twenty or thirty minutes. 

Yet the view that the most quickly-setting cement 
is the best, is found to be quite generally dissemina- 
ted. We read, for instance, in a book on this subject 
of recent date : " Excellent cements, such as the 
Portland cement, Roman cement, and others, if 
immersed in water, harden in a few minutes, while 
inferior cements only attain, after a few hours, such a 



52 SOLUBLE GLASS. 

degree of hardness that they will not take an impres- 
sion by the fingers." 

This view is not quite correct, for it can be proven 
that rapidly-hardening cements will, under other- 
wise equal circumstances, never attain such a degree 
of solidity and strength as slowly-setting ones. 
They will, therefore, not bear the same amount of 
sand. 

Rapidly-setting cements ought, therefore, to be 
avoided when possible, and only used in filling up 
cracks in water works, or for similar purposes : 
firstly, because they fail to attain the same degree of 
solidity and power of resistance as the slowly-setting 
ones ; secondly, because they can only be worked 
with difficult}/ in small quantities, and only giving 
the best result of which they are capable, when the 
mason is exceedingly prompt and skillful ; thirdly, 
because they accomplish much less than they really 
should by being worked in a careless manner, besides 
causing considerable delay. 

For, if the hardening process has once begun in 
the mortar-box, the most assiduous working up of 
the solidifying mass will not (especially if more water 
is added) entirely remedy the evil. 

By employing slow-binding cements, these draw- 
backs are in a great measure avoided. Portland 
cement, which, if mixed with the necessary amount 
of water, say from thirty to forty per cent, in weight, 
and if not setting in less than twenty minutes, will 
scarcely increase in temperature ; quickly-hardening 
cement, however, will get hot in consequence of 



SOLUBLE GLASS. 83 

the rapid chemical action which takes place. Still, 
there exists also limits in regard to slow-setting. If 
it sets too slowly, it remains resistless, and is pressed 
out of the joints, for which reason the continuation 
of the work will be prevented until the mass is 
sufficiently hardened. 

If once set under water, the cement should con- 
tinually get harder without changing its volume, 
cracking, or perhaps, even, falling to pieces. The 
cement should completely fill the mould in which it 
has been prepared as thick paste ; it should not 
suffer any contraction by the evaporation of water 
added in surplus. On the other hand, there should 
be no increase of volume by swelling. 

Hydraulic Mortar from American Limestone. 

These limestones contain mostly lime, silica, 
alumina, oxide of iron and magnesia, which form the 
proper materials for the preparation of mortars ; 
they will withstand the action of water and moisture 
better in proportion, as the quality of silica, alumina 
and magnesia is larger ; they contain forty per cent. 
carbonate of lime, thirty per cent, carbonate of 
magnesia, and twenty per cent, silica, the balance is 
alumina and oxide of iron, and they form a good 
mortar and a good building material ; but when the 
magnesia is to prevalent, will deteriorate it for build- 
ing purposes, it being too friable. The dolomite, 
which is also called bitterspar, a magnesian lime- 
stone, is a double carbonate of lime and magnesia, 



84 SOLUBLE GLASS. 

and abundant in the United States, is a granular 
limestone, and a hardness of 3.5, a spec. gr. of 3. 1, 
and consisting of seventy per cent, lime and nearly 
forty per cent, of magnesia and some oxide of iron 
and manganese ; is unfit by itself as a building 
material, having a great tendency to crumble into 
small fragments, and forms likewise an inferior mate- 
rial for burning and converting it into cement, 
because it lacks the silica indispensable ior this pur- 
pose. By an addition of an alkaline silicate, either 
the silicate of potash or soda, and an addition of 
some alumina, will, after burning, produce a good 
hydraulic cement, particularly in such localities 
where no good native hydraulic limestone is found. 
Not alone France and Germany are particularly rich 
in deposits of hydraulic lime, and in the United 
States likewise, but these in our neighborhood may 
be particularly mentioned at Rondout, on tlu west- 
ern shore of the Hudson River, one hundred miles 
distant from New York. The quarrying in those 
subterranean rocks for hydraulic cement, and also 
common limestone, is carried on in that region, along 
a large extent of the valley of the Rosedale River ; 
through this valley the Hudson and Delaware Canal 
is constructed, which brings the coal from the Lacka- 
wanna Valley at Carbondale, directly to the Hudson 
River. This coal being a very pure anthracite, is 
admirably adapted for use in the limestone and 
cement furnaces situated at the junction of this canal 
with the Hudson River. 

In burning hydraulic limestone, not only the car- 



SOLUBLE GLASS. 85 

bonic acid and water of hydration are drawn off, as 
is the case with common limestone, but after .the 
lime and magnesia have parted with their carbonic 
acid, at the high temperature of the furnace, they 
act on the silica and alumina, as it were, like two 
powerful bases, and a silicate of lime and magnesia, 
as also silicate of alumina and aluminate of lime, are 
formed. The exact chemical reaction during the 
burning process is, however, as v yet not well under- 
stood, and undoubtedly varies in different limestones, 
according to their chemical constitution, which latter 
appears also to very considerably, but without effect- 
ing materially their useful properties. 

In regard to the theoretical causes of the harden- 
ing process, which takes place under water, it may 
be remarked that this curious and interesting pheno- 
menon, being of an entirely chemical nature, has 
largely drawn towards itself the attention, of eminent 
chemists, who have attempted to explain it in ac- 
cordance with well known chemical laws. All 
hydraulic limestones may, by the ordinary method 
of analysis, be decomposed into two component 
parts ; the one consisting of the carbonates of the 
earth, such as lime, magnesia, etc., which, like 
ordinary limestones, yield a fat lime ; the other, a 
silicate, or rather a mixture of the silicates of 
alumina, magnesia, lime, and sometimes potassa, as 
we find in the felspar, which is a silicate of alumina 
and potash, and a greater or less excess of free 
silica ; the latter constituent is, therefore, simply a 
kind of clay. The reaction during the burning pro- 



86 SOLUBLE GLASS. 

cess has been already alluded to. Now, when freshly 
burnt cement is mixed with water, the excess of 
caustic lime as well as the compound into which the 
siliceous clay has been converted during the burning, 
react upon one another in such a manner, that a 
solid stone-like silicate is produced in the humid way, 
the water has a double action ; dry substances, such 
as lime and silicate of alumina, do not act one upon 
another, unless the solvent power of water is brought 
into play so as to bring them into close contact ; 
the water transfers continually the lime it dissolves 
to the silica. The absolute necessity of keeping such 
mortar under water, in order to have it harden, is 
thus explained. Another action of the water is this : 
it enters into a state of hydration in the silicate of 
lime as soon as formed. It must also be observed, 
that the molecular condition of the silica is of the 
utmost importance in this process. Fine sand will 
not combine with lime, when the latter is dissolved 
in water that is in a form known under the name of 
limewater ; but silica, precipitated from a -soluble 
glass solution by means of an acid, which produces 
the gelatinous form of silica, will at once combine 
with the lime in limewater and form a silicate of lime. 
The silica in the hydraulic mortar is also in a state, 
not like fine sand, but chemically combined and 
dissolved in the mass, and therefore, ready to com- 
bine with the lime in limewater. Next in impor- 
tance to silica is the magnesia, which renders the 
lime hydraulic, and which, according to Fuchs, has 
been proved that lime and magnesia, well mixed will 



SOLUBLE GLASS. 87 

harden under water to a certain extent without the 
addition of silica ; for we have in Germany a hydrau- 
lic lime containing only four per cent. When silica 
is found to the extent of fifty-two per cent., the point 
of saturation is reached, and such limestone is no 
more hydraulic. Alumina and iron may be entirely 
absent, although the former is always present in the 
best kinds of hydraulic mortars, of which that of 
Rondout, usually called Rosedale cement, and with 
the employment of which the Croton Water Works 
of New York City were built, is the best on this 
continent. 

It is confidently to be hoped, that by the proper 
application of alkaline silicates will contribute much 
to the manufacture of an artificial hydraulic cement. 

German Hydraulic Cement. 

This material, artificially prepared, is in great use, 
and is of very peculiar composition ; unquestionably 
it is intended to form a silico-aluminate of lime, or 
in other words, an argillaceous silicate, but the 
admixture, such as charcoal and iron filings, cannot 
be explained, but the base being obtained by the 
production of an alkaline silicate, bespeaks for it a 
useful vehicle as a cement. 

It is prepared with twenty-five parts common 
clay, sixty parts lime, ten parts magnesian lime- 
stone, ten parts iron filings, and ten parts of black 
oxide of manganese ; these materials, in very fine 
powders, are made plastic by the liquid silicate of 



88 SOLUBLE GLASS. 

soda, at once applied as a cement or mortar, but it 
will not set at once, six hours being required for the 
mass to harden. 

Stinde proposes the silicate as a very useful cement, 
by mixing equal parts of oxide of manganese and 
oxide of zinc, and making them into a thinish paste 
with the silicate of soda, which paste, quickly applied, 
sets very rapidly ; and by mixing the hydraulic lime 
to this composition, it is a cement which will resist 
permanently also the action of water and heat. 

" Cement and Mortar of the Ancients. 

lk We all know how enthusiastic some are in their 
praises of those ancient structures which . have 
resisted for ages the ravages of time. They imagine 
that they are at liberty to draw conclusions which 
are not the most favorable to the architecture of the 
present time. Although they may be in a measure 
correct, it cannot be denied that such critics are too 
partial in their admiration for things ancient as 
opposed to things modern. We frequently hear the 
remark that some of the Roman mortars have 
endured for eighteen centuries the vicissitudes, of 
time, while many buildings of now 7 -a-days present, 
in a very brief" period, the sign of quick decay ; but 
they forget that these ancient buildings constitute an 
exceedingly small fraction of the enormous number 
of those erected during many centuries in Egypt, 
Greece, Rome and her provinces. They do not con- 
sider that thousands of temples, palaces, and private 



SOLUBLE GLASS. 89 

dwellings have been 1 entirely destroyed. And what 
answer can they assign to the fact that the very com- 
plaints they indulge in -were even more -frequent 
then than now ? Pliny asserts that the reason of 
the falling in of many buildings in Rome, was to be 
attributed to the fact of the bad > quality of the 
mortar. ; ' <■.„•>. . • 

" Still more important than this argument is that 
of Vitruvius, the architect of Augustus. He has left 
a work on Roman architecture in which we find 
nothing that entitles us to place the architects of 
antiquity above those of the present time. Again, 
it has not been taken into account that a great part 
of the extraordinary strength of antique architecture 
is more the effect of time than the mechanical skill 
of the builder, or the virtues of his cements, as we 
propose to show hereafter. Pliny and Vitruvius both 
explain, to the best of their knowledge, what kind 
of materials the builders selected for their cements, 
and how they were prepared. The ; process- was 
identical with the modern modus operandi. It is 
true that the old Romans were particularly careful 
in the selection of materials for their mortar, as well 
as in its preparation. . They were aware that they 
must calcine the limestone, and mix it with sand, in 
order to apply it ; but did not possess any correct 
idea of the change which limestone undergoes in 
the process of calcination, nor of that which is the 
cause of the cohesive quality of mortar. 

"Many centuries elapsed before these facts were 
understood and explained. Black, in 1757, started 



r \ 



go SOiUBLE GLASS. 

the explanatory theory by the discovery of carbonic 
acid. A few years previous to this, Macgraf, the 
discoverer of sugar in beets, found the elements of 
gypsum, which was already employed by the 
Romans ; and, in 1768, Lavoisier demonstrated the 
causes of the hardening of burnt gypsum when it is 
mixed with water. 

" The ancients, therefore, put their practical know- 
ledge to the best possible account. As they were 
deficient in chemical knowledge, they were guided 
only by what observation taught them. Their chief 
care was centered in the exterior. In the selection 
of limestone, the color decided. The white ones 
were considered best, and the colored ones were 
seldom used. Those taken from the interior of the 
earth were preferred to the stones which were met 
with upon the shores of rivers. A law provided that 
the lime must have been slaked three years before i* 
could be used. The same also prescribed the quan- 
tity of sand which must be mixed with the lime, 
mentioning also that crushed cherts imparted a 
greater strength to the mortar. Its preparation was, 
as, it were, a state affair, the censors watching care- 
fully over it. In spite of all this, it often happened, 
as Pliny states, that they did not attain the object in 
view. 

" But in the advance of chemical science, the fact 
has been established that a mortar can be prepared 
that, in the course of one or two years, will be as 
strong and durable as Roman mortar after the lapse 
of two thousand years. The builders of the ancients 



SOLUBLE GLASS. 91 

were not further advanced than those of the middle 
ages. The walls of the Bastile, for instance, were 
so strong that they had to be blasted away. This 
had likewise to be done in the removal of the rem- 
nants of a bridge at Agen, built about the year 1200 ; 
and the mortar of a bridge erected at Calhours in 
1400 was even found to be considerably stronger 
than that of the antique theatre of the same city. 

" The Romans were also acquained with hydraulic 
cement. The merit of this knowledge is, however, 
considerably lessened, when we consider that the 
same is found in the volcanic districts of Southern 
Italy. A mere accidental observation, the same 
being, perhaps, mixed with sand instead of lime, 
may have led to its application. Says Vitruvius : 
* There exists a kind of dust which produces strange 
things ; it is found near Baja and the Vesuvius. 
When mixed with lime, it forms a mortar which not 
only imparts great strength to buildings, but also to 
w r ater works.' 

" The natural cement in question is a volcanic 
pumice-stone, like breccia, which is still found in the 
environs of Naples. At a less remote period of time, 
when the Romans invaded the valleys of the Lower 
Rhine, they easily recognized the volcanic nature of 
the Brohl Valley. Here, as well as amid the sur- 
roundings of the beautiful Laacher Lake, which lies 
like a jewel set in the midst of the long-extinct 
Rhenish volcanoes, they discovered another natural 
cement — the trass — in such considerable quantities, 
that the quarries which were opened at that time 



92 SOLUBLE GLASS. 

are still in existence. The use of hydraulic cement 
in ancient times could, therefore, have been only a 
limited one, as it was found only at the two places 
mentioned. Its artificial preparation was not under- 
stood. The solution of this problem was reversed 
for the investigating minds of the present progressive 
century." , 

" The Uses of Hydraulic Gemenl. 

" It is justly esteemed far superior to metal for the 
lining of cisterns, the water-proofing of cellar bot- 
toms, and similar purposes. A few directions for its 
preparation and use may not be out of place. To 
make water-proof work, it must be borne in mind 
that common lime must not be used at all ; for on 
common lime, water or moisture has an effect just 
the opposite to that which it has on the water lime, 
rendering it soft and quite friable when dried ; whilst 
on the water lime the well known effect is to make 
it perfectly hard. No mixture of these two varieties 
of lime can, therefore, be made under water. But, 
although they do not act well 'together, even under 
ground, they serve well in dry places, such as build- 
ings whose walls are of extra thickness ; and if 
proper care be taken, they will conjointly form a 
very compact and powerful cement. The fact that 
water lime shrinks when wet, while cqmmon lime, in 
the same state, swells, at once points out the manner 
of treatment to be pursued in . uniting the two 
thoroughly. Thus, it is necessary to ascertain the 



SOLUBLE GLASS, 93 

percentage of shrinking of the one and increase in 
the other, as nearly as possible, before the propor- 
tion of one. to the other can be determined, with a 
view to their intimate combination. Such experi- 
ments are the more necessary when we consider the 
great difference which exists in the quality of both, 
kinds of lime in various localities; The simplest and 
most effectual mode of testing water lime is to put 
several portions of different makes into small bags 
of flannel, and .throw them into a basin of water. 
After three minutes' immersion, take them all out at 
once, and squeeze each in the hand. : Then, take off 
each bag, and that which is best is firmest, and 
when thrown naked into the water again, loses least 
of its outer case. If none of them will bear uncover- 
ing at three minutes, try four, five minutes, but this 
latter should be the longest test. The test for com- 
mon lime is, on the contrary, the bursting open and 
evolving of chloride in a greater or less degree ; and 
the consequent action of the water will show, by its 
bubbles, the power of the lime, 

" It. is the percentage of clay contained in any 
specimen of lime that determines the solidifying pro- 
perty of the cement made from it. The best 
hydraulic lime contains silex, lime and magnesia, or 
alumina. Its solidification is attributable to the 
formation of silicate, of alumina and lime, or of map - - 
nesia and lime, which combines with water, and 
produces a hydrate excessively hard and insoluble in 
water. The hardening of hydraulic lime may, then, 
be compared, to that of calcined plaster, which also 



94 SOLUBLE GLASS. 

combines with water to form a solid hydrate ; which 
calcined plaster, from the large quantities of it 
manufactured near that city, is commonly known as 
plaster of Paris. A limestone containing thirty per 
cent, of clay makes a quick-setting cement ; and we 
have in the United States the Rosedale and the 
Bellville cements, having forty and fifty per cent. 
They become exceedingly hard when plunged in 
water for from two to three minutes. Both these 
cements, especially the former, have been used 
extensively by our engineers. 

" Inferiority in the quality of hydraulic lime may- 
be produced by the want of proper care during its 
manufacture, the stone being calcined at too high a 
temperature ; the double silicate in such case becom- 
ing a sort otfrit, which does not hydrate in contact 
with water. 

4 'As hydraulic lime is expensive according to the 
distance of its transportation, we will here give the 
method of making an artificial hydraulic lime, accord- 
ing to the highly successful experiments of M. Vrcat, 
a celebrated French engineer, and the author of a 
much esteemed work on hydraulic cement, who first 
showed the method to be adopted in its formation. 
It is prepared by stirring into water a mixture of one 
part of clay and four parts of chalk ; these materials 
should be mixed by a vertical wheel turning in a cir- 
cular trough, and made to flow out into a large re- 
ceiver. A deposit soon takes place, which is formed 
into small bricks, which, after being dried in the air, 
are moderately calcined. Hydraulic lime thus pre- 



SOLUBLE GLASS. 95 

pared enlarges about two-thirds in volume when 
placed in water. Like the natural hydraulic lime, it 
can be completely dissolved by acids. This invention 
of artificial hydraulic lime has rendered Vicat de- 
servedly famous, as it has been in use for many years 
in the public works throughout France, and was even 
employed in the hydraulic masonry of the St. Martin 
Canal. That it can be made in this country, there is 
no doubt, as the argillaceous or potter's clay required 
is to be found almost everywhere. 

The new cement which M. Sorel proposed to the 
French Academy consists in the application of basic 
hydrated oxychloride of magnesium, may unquestion- 
ably be improved by means of a silicated hydraulic 
lime and the bittern of the salines, which is a chlo- 
ride of magnesium in a concentrated condition. 

Many important facts have come to light by the 
investigations made on hydraulic limes and artificial 
stones, which prove that a considerable quanity of 
potash is contained in the natural hydraulic and other 
cements ; the origin of which is attributed to the 
decomposition of the alkaline silicates by the lime, 
and this may be proved by the formation of saltpetre 
or nitrate of potash in the efflorescences of walls and 
earths in caves, called an eremacausis of substances 
which contain nitrogen, and form, therefore, ammo- 
nia, and in contact with porous substances undergo 
an oxydation and conversion into nitric acid, and at 
once is combined with the alkalies contained in the 
native lime occurring in the older formations, and 
was seprated, under certain circumstances, from the 



g6 SOLUBLE GLASS. 

alkaline silicates found in those limestones— nitrate 
of potash is result. In general terms, nitre, or ni- 
trate of potash, which is found in crusts on the sur- 
face of the earth, on walls and rocks, and in caives, is 
found in those localities in certain soils of Spain y 
Egypt, Persia and East Indes, especially in hot 
weather succeeding rains ; is is also manufactured 
from soils where other nitrates (nitrate of lime or 
nitrate of soda) form in a similar manner, and beds 
called nitraries are arranged for this purpose in many 
countries. Refuse animal matter also, putrified in 
calcareous soils, gives rise to nitrate of lime, as we 
find it so frequently in cow and horse stables, and is 
then converted into nitrate of potash ; old plaster 
walls, when lixivated, afford about 5 per cent, of 
nitre. It is known that nitre requires for its form- 
ation dry air and long periods without rain ; the potash 
comes mainly from the debris of felspathic and lime 
rocks in the soil, or in the cements ? if they have been 
used for building walls, and the oxydation of the nitro- 
gen of the air is promoted by organic matter, hence 
the nitre is generally associated with azotized de- 
composed organic substances. A nitre crust from the 
vicinity of Constantine, Algeria, afforded Boussingault 
85 per cent, nitrate of potash, with some nitrate of 
lime, soda and magnesia. In the Mammoth Cave of 
Kentucky, where the nitre is found scattered through 
the loose earth in great abundance, and was utilized 
during the war of 18 12, also in the Mississippi Val- 
ley, in Missouri, many caves have yielded the nitre 
which was of great use to the Secessionists of the 



SOLUBLE GLASS. 97 

\ 
late war, when Tennessee, along the limestone slopes 
and in the gorges of the Cumberland table land, pro- 
duced a large amount of saltpetre. 

The nitrate of soda, formed in a similar manner 
like that of nitrate of potash, but more particularly 
is found in the dry pampas of Chili, where it is found 
at a height of 3,300 feet above the sea, contains beds 
of several feet in thickness, along with gypsum, 
common salt, glauber salt, and the remains of re- 
cent shells, indicating the former presence of the 
sea. 

Respecting the cement which is formed by the 
moist way, it is a fact that when chalk is brought in 
contact with solutions of alkaline silicates, an ex- 
change of the acids of both salts takes place, one 
part of the chalk is converted into silicate of lime, 
and the corresponding quantity of potash in carbon- 
ate of potash ; this explains the true artificial stone, 
which has become, on exposure to the atmosphere, 
so hard, trSat, if the mixture contains a sufficient 
quantity of a silicate, possesses the property to adhere 
firmly to such bodies where it has been applied, the 
materials so formed with the silicate of potash of 
soda are analogous to cements without burning, and 
may be used for restoring monuments, etc. In the 
silicification of artificial stones, the affinity of lime to 
the silica contained in the soluble glass is manifest, 
and shows the effect of the alkaline silicates on lime- 
stones ; and how the influence of the atmosphere in 
the hardening of silicates or artificial limes is brought 
to bear through the atmospheric carbonic acid by the 



98 SOLUBLE GLASS. 

separation of one part of silica in the silicates, and 
how the other parts of the silicates, when in close 
contact with a sufficient quantity of carbonate of 
lime, a lime silicate is formed. 

This acquired knowledge has produced numerous 
applications in industry ; it has proved that, by arti- 
ficial impregnation of mineral substances into the 
interior of porous substances, organic as well as 
inorganic matters are preserved or silicified. The 
silicification of fine sandstone is easily effected by 
the mixture of one part of liquid silica, and two 
parts of fine sand, with the addition of a small quan- 
tity of chalk and white clay, all of which are wrought 
into a paste, and then formed into desired objects 
and exposed to the atmosphere for some- t me, and 
the finishing process continued by means of hydraulic 
pressure and heating in hot chambers, the particulars 
of which have been indicated in a former chapter. 
It has been ascertained that always, if any 
salt insoluble in water is brought in contact with the 
solution of a salt which forms with the acid of- the 
base of the insoluble salt a less soluble substance, an 
exchange takes place, which, although but partial 
sometimes, produces the formation of double salts . 
This discovery led to a direct application that white 
lead, chromate of lead, chromate of lime, and the 
majority of the carbonated metallic salts, are suit- 
able for silicification. 



SOLUBLE GLASS. 99 

SILICA PAINTS. 

The uses of soluble glass in paints and colors, in 
order to produce a fine covering inside and outside 
of houses, fences, etc., which is intended not alone tor 
ornaments, fire and water proof, but also economical 
and within the reach of the middle class of people, 
have as yet not been general, and the few manufac- 
turers of a fire proof and ornamental paint of intrinsic 
value, have realized, deservedly, large fortunes and 
continue to do so. The difficulty of producing a 
good paint, containing linseed oil and spirits of tur- 
pentine,, with the required pigments, and the addition 
of soluble glass, lies in the incompatibility of oil, 
water and turpentine, their separation after they 
have all been mixed together for some time. 

The experiments undertaken to introduce an 
alkali or alkaline earth, as a vehicle, have not all 
proven successful. One fact has been ascertained, 
that a small addition of neutral substances which will 
be noticed presently, will assist the uniformity and 
permanency, and from ten to fifteen per cent, of the 
concentrated soluble glass may be added to a mixed 
paint, with proper mechanical applications and 
knowledge of such pigments, which from their 
chemical constitution will decompose each other and 
form new compounds. 

I will state here as a fixed fact, that the secret of 
mixing the paints so as to make them of service, 
lies in the oxidation of metals, and the production 
of the oxides. Most of them are called bases, and 



100 SOLUBLE GLASS. 

if then combined with acids, are called salts. Chalk, 
whiting and Paris white, are oxides of the metal cal- 
. cium and these combined with the carbonic acid, form 
the carbonate of lime. Ochres and allied pigments 
such as sienna, umber, colcothar, Venetian red, and 
many similar colored paints are but oxides of the 
metal iron ; so is white lead, red lead, litharge 
the oxides of the metal lead. All these oxides 
and many more are capable of being assimilated 
with linseed oil by trituration, and the addition of 
spirits of turpentine, intended as an economical 
vehicle, requires some caution to its admixture in 
order to make the concentrated liquid soluble glass 
fulfill all its requirements in place of spirits of tur- 
pentine, which, in truth, does little or no service in 
thinning all the pigments, such as lead, zinc, ochres, 
etc., and has no other virtues ; while the soluble glass 
does possess many, which improve the pigments. 
While the spirits of turpentine may consume one 
pound of the latter to eight of the ground pigment in 
linseed oil, a much larger quantity of the soluble 
glass may be mixed with the pigments of lead and 
zinc, or precipitated sulphate of baryta,, which is 
called blanc-fix, and which will bear mixing with all 
the other white and colored pigments. 

Another advantage of the admixture of the con- 
centrated soluble glass is economy. One hundred 
pounds of pure white lead ground in oil, require six 
gallons of linseed oil to thin it to a proper consist- 
ency for making a first coat on new or unpainted 
pine wood ; six gallons of linseed oil and after- 



SOLUBLE GLASS. ICl 

wards five gallons linseed oil at the second paint- 
ing ; and if zinc white is intended for painting 
pine wood, ten gallons are required for the last coat, 
the soluble glass will replace nearly one-half 
the quantity of linseed oil. A similar economy is 
used in colored paints ; for french ochre requires 
about twice its weight in oil, or v twenty-five gallons 
to one hundred pounds dry material. It is also very 
interesting to know that the addition of soluble 
glass assists much in spreading over a larger sur- 
face, for one hundred pounds of pure white lead paint 
will cover a surface of four hundred square yards of 
planed pine wood for out door work, and of pure zinc 
white one pound will cover five square yards, and 
of yellow ochre one pound eight square yards, and 
of Venetian red one pound to seven square yards, 
while the addition of the syrup (concentrated) solu- 
ble glass will save twenty-five per cent. 

There are many mineral colors which will easily 
mix with the soluble glass, while vegetable colors con- 
taining free acids will be incompatible; the oxide 
of manganese, sulphide of cadmium, oxide of 
chrome, ultramarine and many natural earth paints, 
can be united with the soluble glass. 

The safest plan of preparing the soluble glass for 
such pigments, is to add first a small portion of 
porus alum, sulphate of alumina, or chloride of 
calcium. White clay or Paris white, in the finely 
divided condition may likewise be added previous to 
the addition of the desired pigments in the paint 
mill, this must be done in small portions to the* 



102 SOLUBLE GLASS. 

paints already treated with oil ; it requires no spirits 
of turpentine ; the paint so produced will dry quite 
as quick as if the paint had been diluted with the 
latter liquid. 

It is well known that linseed oil is the only vehicle 
suitable for mixing and spreading paints, whether 
simple or compound. It is superior to all other fixed 
and fatty oils, because it does not undergo a chemi- 
cal change, does not become rancid like vegetable 
oils in general, nor does it emit any unpleasant 
flavors like mineral oils ; neither does it thicken 
and become viscid, unless exposed to high tem- 
perature, but remains limpid under ordinary 
temperature ; nor does it congeal till cooled to about 
twelve degrees below zero. The only drawback to 
the addition of linseed oil to dry paints is, that they 
are rendered less opaque and give them a tint ; in 
other words when mixed with white lead which is 
opaque it is rendered semi-transparent and assumes 
a yellowish tint, which fault can be remedied by the 
addition of some white pigments ; like white oxide 
of zinc, pure whiting, or Paris white. By resorting to 
the previous bleaching of linseed, either by exposure 
to direct sun light, heating it to a certain tempera- 
ture or treating it with sulphuric acid, and washing 
the same mixture with steam, it is proven that the 
small benefit of withdrawing a small portion of the 
coloring principle so as to produce a paler tint, never- 
theless, it does not undergo any other change, 
as it does not improve its siccative property, but 
adds much to the cost of the material since it 



SOLUBLE GLASS. 103 

decreases in bulk, and we may as well come to the 
conclusion that no pigment is improved either in 
density, covering or spreading, if mixed with 
either linseed or any other oil. The main dependence 
of a pigment is its quality, and any oil which is then 
mixed with it most possess the property of drying 
quickly, without sticking, must be indorous, color- 
less, limpid ; must not congeal or discolor nor turn 
yellow when not exposed to the atmosphere, and 
must be entirely water proof. The addition of solu- 
ble glass to linseed oil can only be effected by 
adding in small portions, to the pigment and linseed 
oil in the mill, on coming out from the mixing tubs. 

Soluble Glass in White Paints. 

White lead, white oxide of zinc, white oxide of 
antimony, white oxide of .tin and sulphate of baryta, 
precipitated from its salts ; native sulphate of baryta, 
native carbonate of baryta, artificial chloride of 
barium, Paris white, whiting, kremnitz white, terra 
alba or sulphate of lime and of plaster Paris, china 
clay, talc, etc., form the principal substances 
which are used, either by themselves or as adulter- 
ations or admixtures, to those standard white metal- 
lic oxides which have for centuries been employed as 
a coating of wood, stone or brick, for either inside or 
outside painting or for ornamenting the inside of houses 
and palaces. It is well known that none of the 
above named white pigments are employed without 
the addition of one or more of the aforemen- 



_ 



104 * SOLUBLE GLASS. 

tioned articles. White lead and white oxide of zinc, 
if mixed in certain proportions, will produce a better 
paint than the simple materials in combination with 
linseed oil, for it is said that the mixed paint pre- 
serves its whiteness well, works smoothly and easily 
under the brush, and gives a uniform coating to 
wood, plaster or stone. 

If white lead is employed pure it takes about one 
gallon and a half of linseed oil to one hundred pounds 
of the lead ; but if the white oxide of zinc is 
added, it takes but eighty pounds of white lead and 
twenty pounds white zinc for one gallon and a half 
of oil. 

The common white lead of commerce, contains 
from twenty-five to fifty pounds of sulphate of baryta" 
to the above mixture, and if the soluble glass is 
added half the quantity of linseed oil is required, 
and may be thinned with another half gallon in 
place of the spirits of turpentine usually employed. 
The precipitated stdpliate of baryta is preferable to 
the native mineral generally called baryta, and it 
may now even be likewise added to the above 
mixture of white lead and zinc, which will much 
improve the finished paint. 

This pigment is generally called permanent white. 
It is prepared either from the native mineral, called 
barytes or from the native carbonate of baryta 
called witherite, and more recently from chloride 
of barium, a waste product obtained from the gas 
houses where the chloride of ammonium, chloride of 
calcium and then the chloride of barium is obtained. 



S OLUBLE GLASS. 105 

which is then precipitated by oil of vitriol or glau- 
ber salt as a fine white powder, which possesses a 
fine white lustre ; it is fit to be mixed by itself with 
soluble glass, or in combination with either white 
lead or zinc white, it is not subject to tarnish in 
dwellings ; "when exposed to hydro-sulphuric acid, 
which mostly attackr white lead. It may also be mix- 
ed with dexterine, starch or other binding material, in 
connection with soluble glass. So far it has not been 
much employed for this purpose, but it bids fair, 
when its superior qualities are once appreciated and 
experiments shall have proven its usefulness for 
painting the outside and inside of dwellings, to find 
a large consumption among the painters of this 
country. 

Soluble Glass in Colored Paints. 

It is quite natural that economy is as important in 
painting as in all other trades, and, as thebeforemen- 
tioned white paints may be too expensive for a 
general use, the introduction of soluble glass is the 
first step to economy, which, with good judgment, 
may be used not alone with the various white pig- 
ments, but also among colored paints, either by 
themselves or mixed w r ith others. It will be found 
applicable when combined with the soluble glass 
and may find a suitable place in the arts. The 

Black Paint 

are very suitable for mixing with soluble glass, 
calcined lampblack, drop black, Frankford black and 



IOD SOLUBLE GLASS. 

bone black (called patent black), and will produce a 
fine paint, which adheres and dries quickly ; it may- 
be used for blackboards for schools, sign boards, ship 
painting and for printers ink. 

The vegetable and animal black pigments are 
more permanent than any other pigment, and will 
resist better atmospheric and chemical actions than 
any other color. The 

Green Paints 

are very numerous, but, with few exceptions, are not 
suitable for a combination with soluble glass. In 
some instances they have been tried and found to 
answer the purpose. The Brunswick green and mag- 
nesia green, are varieties of chrome green. The 
copper greens, such as blue and green verditer, which 
are, properly speaking, a carbonate of copper, will do 
very well to produce a pigment if diluted with soluble 
glass. The Paris green and verdigris, the first 
an arsenite and the other an acetate of copper,- are 
altogether incompatible with soluble glass. The 

Blue Pigments 

arc also very common, and mostly fit for mixing 
with soluble glass, such as ultramarine, which is 
prepared from alumina, sulphur and soda, is a 
most beautiful pigment, and will mix readily with the 
soluble glass. The blue smalts, deriving from oxide 
of cobalt, will also mix with soluble glass. Neither 



SOLUBLE GLASS. \OJ 

the Prussian nor Antwerp, nor indigo blue, will mix 
with soluble glass. 

The most numerous pigments are the red, and its 
many shades, and derived from the animal, vegetable 
and mineral kingdoms. Few 5 however, are fit to mix 
with soluble glass. The 

Carmine 

is the prettiest of these red pigments, and is pre- 
pared from the insect called cochineal, and is pre- 
cipitated by alum from its watery decoction. It will 
do to mix with soluble glass as a pigment. The 
American vermilli.on, so called, is a compound from 
chromic acid and white lead, and will not answer 
with soluble glass as a pigment. 

Venetian Red 

is a beautiful earthy color, an intense permanent 
color, is most durable, and forms a good base with 
other colors. It makes a very good mixture with 
soluble glass, 

Indian Red 

is likewise an oxide of iron, and like the last men- 
tioned, is a permanent pigment, and is principally 
used-with white paints to produce a gray color ; also 
with ultramarine. It mixes well with soluble glass. 

Red Lead, 

which is a pure oxide of lead, is much employed by 
painters as a dryer, and can be mixed with soluble 



i08 soluble glass. 

Light Red Earth 

is used as a body for other mixed paints , and is obtained 
by calcining yellow ochre. It will easily mix with 
soluble glass. All vegetable colors, such as rose 
pink, pulp colors and will not mix with soluble glass. 
Among" the 



x i=> 



Yellow Colors 

which yield a fine pigment, the cadmium yellow 
rivals the chrome yellow. The first may be easily 
mixed with the soluble glass, while the chrome yel- 
low will not do it. 

Yellow Ochre, 

is a native pigment, an earthy yellow, is the most 
permanent color, and resists the action of atmos- 
phere and rain most wonderfully ; soluble glass will 
readily mix with it, and produces fine shades with 
white paints. The 

Brown 

pigments are not very numerous, but produce a per- 
manent color, and mixible with soluble glass. 

Sienna 

both raw and burnt, is an esteemed colors, and pro- 
duces a transparent pigment with soluble glass it 



SOLUBLE GLASS. ICQ 

mixes well ; when burnt it turns to a deep brown- 
r£d color. Raw sienna will produce an alive green 
when mixed with indigo, but then it cannot be mixed 
with soluble glass, while otherwise it will readily 
do so. 

Umber 

is another species of ochre, is a brown pigment ; it 
is easily mixed with soluble glass, and as it contains 
as a constituent the per oxide of manganese, forms 
an excellent dryer. It is very extensively used in 
painting. 

Burnt Umber 

is the calcihed raw umber, is considerably used by 
painters, being a permanent and transparent pig- 
ment. It mixes readily with soluble glass. 

Van Dyke Brown. 

It is an earthy brown color, and a specie of shale, 
largely used by painters, and soluble glass will mix 
well with it ; it is a very permanent and favorite color. 

Spanish Brown, 

likewise an ochre of brown color, is much used in 
painting outside work, and forms a dense body ; is 
. often the calcined product of common ochres, obtained 
in this country ; it will produce a good pigment 
when mixed with soluble glass. 



110 soluble glass. 

Silico-Black Lead Fire Proof Paint. 

Soluble glass will readily mix with plumbago and 
colcothar, a clay, and will protect iron buildings and 
roofing, iron railing and fences, from rust or 
oxidizing ; this paint, if properly prepared, will 
render all wooden structures uninflammable and fire 
proof. If the paint is properly applied, smoke stacks 
on steamers will resist the usual exposures of smoke, 
steam and hot water for years. 

The best method of preparing this valuable silico- 
plumbago paint is the following : To one hundred 
pounds of Venetian red, add fifty pounds fine Ger- 
man blacklead, ten pounds of clay and ten pounds 
oxide of manganese. These three substances are 
ground up in the paint mill with five gallons of rosin 
oil and ten gallons of soluble glass, forty-two 
degrees B. When uniformly ground, add twenty 
pounds finely ground and calcined lamp black, or 
fine boneblack. This paint will be fit for use, as soon 
as prepared and will dry within a few hours after its 
application. In order to produce a more intimate 
combination of the soluble glass, with the rosin oil, 
it is well to add about five pounds of porous alum 
(sulphate of alumina without any alkali) in the mix- 
ture which is to go into the mill, and it will produce 
a more uniform composition. 

General Rules for the uses of Soluble Glass 
in all kinds of paints. 

All paints whether white or colored, for priming 



SOLUBLE GLASS. Ill 

or finishing whether intended for inside or outside 
painting, or for wood, iron, stone or brick, may be 
mixed with the liquid soluble glass, and under proper 
management, may be made to unite with linseed oil, 
rosin oil and fish oils, or other incongruent sub- 
stances. It requires an intermediator, which consists 
in adding either the chloride of calcium, sulphate of 
alumina, known as porous alum, whiting, or Paris 
white, finely powdered clay, talc or soapstone, and 
many more vehicles, already indicated, like chloride 
of barium, which either act chemically or me- 
chanically to absorb the alkali of the soluble 
glass, and unite silicic acicl with the pigments, and 
form thereby a new compound which may be mixed 
with any oil in the mill and produce a uniform sub- 
stance suitable for paint. 

Soluble Glass for Black Boards and Silica 

Slates. 

Largely used in schools and for pocket slates. The 
soluble glass is applied with black lead and finest 
ivory black, formed into a paste first by a little boiled 
linseed oil, which is afterwards diluted by soluble 
glass to a thin liquid and then applied to the smooth 
board. Black aniline diluted with soluble glass and 
mixed with Frankford black may be made to answer 
the purpose, 

Umber and Sienna Colors. 

All ochres, whether the Virginia, North Carolina, 
Georgia, or eastern ochry minerals, when finely 



112 SOLUBLE GLASS. 

ground may be mixed with soluble glass, and produce 
fine paint by itself ; as is the same with umber and 
sienna. The addition of white oxide of zinc and 
finely ground chloride of manganese produce the 
finest shades. 

Soluble Glass as a coating for Wooden Floors. 

It is well adapted for wooden floors in stores, offices, 
public and private buildings. Before applying the 
coating, the floor should be well cleaned, and the 
spaces or interstices between the boards be filled 
with a mixture of soluble glass and chalk, or gypsum 
made into a thick dough, which will quickly set 
into a hard mass. The floor may then be brushed 
over with a solution of the soluble glass at thirty 
degrees B. If colors are employed, most vegetable 
pigments must be avoided, on account of the alkali 
contained in the soluble glass. The mineral colors 
used, should be ground with equal parts of water 
and skimmed milk, before they are mixed with the 
soluble glass. It is applied with a stiff brush and as 
it dries quickly, a second coating may be put on in 
half an hour. In order to give the flooring a brilliant 
polish, a third coating with any vegetable oil or 
varnish may be applied. The floors are protected 
against fire, and if colors are used, renders them 
quite ornamental. 



SOLUBLE GLASS. II3 

PRACTICAL SILICATE PAINTING. 

Wood may be painted by covering it first with a 
chalk ground, which must be thick enough to allow 
a polishing with pumice ; to chalk, glue or a little 
silicate solution may be added, as a binding material. 
Another difficulty occurs after the first has been 
overcome, in the oozing out of the carbonate of 
soda in damp weather, until the whole salt has 
been expelled, and many experiments have failed. 
Hydrochlorate of ammonia was first proposed in 
a weak solution, and an absolute insolubility of the 
color was thereby obtained ; but chloride of soda 
remained in this operation, which destroys the gloss 
of the colors if not at once removed by repeated 
washing ; forced to resort to those few chemical 
agents, apt to fix the soda, which should enter as 
insoluble combinations in the color without destroy- 
ing them, the perchloric and hydrofluoric acids were 
resorted to. It is well known, that by washing with 
hydrofluoric acid the density of the colors is much 
increased, and it w r as thought, therefore, safe to use 
it, particularly in painting on glass, but only as a 
very weak solution. Hydrofluoric acid possesses the 
most remarkable property to dissolve most oxides 
w r hen in a concentrated state. The application of 
the weak solution of hydrofluoric acid, either for 
fixing the soda in painting and in silicification of 
limestone, was mainly calculated for such cases where 
a silicate has been used' with an excess of soda ; 
and in the hardening of soft and porous limestones be a 



114 SOLUBLE GLASS. 

partial conversion into a lime silicate, it was found 
very expedient for fixing the soda and making- 
sure the insolubility to moisten, at first with a weak, 
and then strong solution of the hydrofluoric acid, the 
stones when the soda oozed out. The acid, how- 
ever, penetrates the stone and produces an insoluble 
compound ; in other words, it fixes the soluble com- 
pound. Through this discovery hydrofluoric acid 
was found a very useful application in the fluosili- 
cated lime. 

If brought into contact with lime, hydrofluoric acid 
is capable of dissolving it cousiderably without pro- 
ducing an immediate precipitate of calcium, or a 
separation of the silica ; but at a certain state of 
saturation any addition of lime decomposes entirely 
the hydrofluoric acid, and so much that not a trace 
of these bodies can be discovered in the fluid. The 
same results are obtained by the carbonate of lime, 
instead of the caustic lime, and that silicium and 
fluor are produced in the limestone, which hardens 
but -slowly, and it is therefore simply a fluorsilicon 
that produces the hardening of the lime. The effect 
of the hydrofluoric acid on gypsum is also produced 
in both mixing, the surface of the gypsum is 
considerably hardened. If, however, the acid is used 
in excess, the gypsum is covered with raised pustu- 
les, which owe their existence to the formation of 
bisulphate of lime, because sulphuric acid does not 
act as well as the carbonic acid does in the treat- 
ment of limestone ; a flu'or-calcium, mixed with 
soluble glass, may be used as a paint, or paste, or 



SOLUBLE GLASS. 1 1 5 

cement, or any coating of other substance, and be- 
comes so hard and weather-proof that neither soda 
nor potash will detach from the combination, and 
will remain dry. 

Painting on Metals, Glass and Porcelain. 

Silica painting adheres strongly on metals, pro- 
vided care is taken to keep the substances some time 
from the contact with water. The most durable 
paint is produced on zinc, also on porcelain and 
glass ; the colors assume a semi-transparency if 
painted on glass, and no doubt afford much induce- 
ment for its use. The sulphate of baryta, artificially 
prepared, combined with silicate, applied to glass, 
makes a milky white appearance, and is very beauti- 
ful, as it incorporates very intimately with the silica, 
so that after the lapse of a few days the paint cannot 
be removed even with warm water. If this glass is 
exposed to high heat, (six degrees Wedgewood), a 
fine white enamel is formed on the surface, which 
will compare well with the oxide of tin, and is much 
cheaper. Ultramarine, oxide of chrome, if conver- 
ted into enamels, form a prolific source for the new 
art of painting. It is not quite necessary that a 
chemical combination should be produced in all 
these colors, if they only adhere strongly and pro- 
duce the silicated cement, which has become hard 
by its fine division and easy admission of air. 

Emery, sesquioxide of iron and peroxide of man- 
ganese, if finely powdered and prepared with a con- 



Il6 SOLUBLE GLASS. 

centrated solution of soluble glass, produce cements 
of extraordinary hardness, resisting the effect of 
heat completely, and become perfectly insoluble in 
water. 

For the production of an indestructible ink, solu- 
ble glass has been used and obtained by mixing 
finely burnt lampblack with the liquid soluble glass. 
Braconnof s ink is prepared by decomposing leather 
in caustic potash, and adding to the black mass the 
liquid soluble glass. A decoction of cochineal mixed 
with the liquid soluble glass, produces a red ink, re- 
sisting completely the action of chlorine and all 
other acids. 

The Best Permanent and Inerasible Ink. 

To one hundred pounds finest vegetable black, 
add five pounds liquid ammonia and rub or triturate 
well together with 2 gallons silicate of soda, and dilute 
the whole with three gallons of water, or so much 
as to make a thin liquid suitable for writing. This 
ink when dry will not be attacked by acids, chlorine 
or alkalies, 

Silicate of Soda in tlie Production of Gold, 
Silver and Aniline Inks. 

In place of shell gold and shell silver, which have 
hitherto been the only materials for obtaining colored 
inks, the Mosaic gold, which is a sulphide of tin, and 
the iodide of lead and Dutch leaf, are mostly employed 



SOLUBLE GLASS. 117 

for a gold ink, while the genuine silver foil is used 
for silver ink. The commercial bronze powder is 
triturated with a little honey to a thin paste, which, 
when finely rubbed up, it is put into a glass and boiled 
by steam and water, containing some alkali, and 
stirring it frequently, when it is decanted and well 
washed with hot water and then dried at a gentle 
heat. By boiling the powder with water containing 
sulphuric, nitric or hydrochloric acid, different 
shades are obtained. 

To produce the proper inks proceed as follows : 
Dissolve one pound of white gum arabic in four 
pounds of pure water, to which one pound of 
soluble glass of forty-two degrees B., is added and 
triturated with about one pound purified metallic 
powders or pigment. Gold ink will bear more liquid 
than silver, and also covering much better than 
silver. On rough paper, more metal is necessary 
than on sized papers, and on light paper more than on 
dark paper. In order to make the colors of the ink 
appear equally intense, one part of the original foil 
is bronze to three or four parts of the liquid ; it 
must be continually stiored and equally divided. It 
requires frequent stirring and it is best to mix the 
dry powder with the liquid immediately before using, 
and it may be done with a steel pen or pencil. The 
advantages which the application of soluble glass 
furnishes are important. It greatly increases the me- 
tallic lustre on paper, prevents its looking dull and 
will protect the writing from being discolored by the 
atmosphere ; and it prevents its penetrating too far 



Il8 SOLUBLE GLASS. 

into the pores of the paper, without rendering it very 
viscid. The metallic lustre may be increased by 
gently polishing with a polishing steel. 

A red ink may be made of one part fuchsine and 
one hundred and fifty parts boiling water. A green 
ink is obtained by dissolving one part of iodine green 
in one hundred and four parts boiling water. The 
aniline inks are not fit for copying. 

A White Cement or Base for Inside Walls 
Breweries and Cellars. 

Take a white wash brush and apply the soluble 
glass in its concentrated state. Before the coat- 
ing becomes quite dry, apply with a brush, a solu- 
tion of porous alum, composed of one pound of 
alum to three pounds of hot water. The same will 
dry soon, and become a permanent cement, and may 
then be painted over, or left without painting. 

Silicate of Soda for Enamel. 

Firebrick, furnaces, and hearths may be made 
vitreous by the application of soluble glass, so as to 
form an enamel, by dipping the individual firebrick, 
or other articles, in the liquid and letting it dry before 
exposing the substances to be enameled or glazed to 
the fire. 



soluble gass. ii9 

Soluble Glass as a Medicine. 

In the treatment of gout and rheumatism, for 
the purpose of eliminating uric acid by the urine. 
It is supposed to promote the discharge of uric 
acid by the kidneys, and when combined with ben- 
zoate of soda transforms the uric into hippuric acid. 
For producing an alkaline reaction of the urine, 
soluble glass is also highly recommended. 

In case of certain fractures of the limbs and dis- 
eased joints, as immoveable dressings, it may be ap- 
plied by means of a brush to the bandages. It hard- 
ens. quickly and will dry in five or six hours. 

Also as a substitute for starch, dexterine and plas- 
ter of Paris. 

A Concrete Pavement. 

This pavement is composed of seventy per cent, 
in bulk of broken stone, coal or gravel, clean 
coal or iron cinders, not over three inches in 
any dimensions. These are passed over a screen 
with meshes one quarter inch square. The coarser 
portion is then coated by mixing with tar, warm or 
cold, and then spread on the road-bed and heavily 
rolled until a depth of four inches is attained. The 
finer portion is then mixed with clean sharp sand, 
warmed, and then thoroughly mixed with tar, to 
which has been added rosin, carbojapanis or pitch. 
This is placed on the first layer of coarse material, 



I2G 



SOLUBLE GLASS. 



and rolled until a depth of two inches is attained ; 
after which the surface is covered with an excess of 
clean, sharp sand, and again rolled. 



CEMENTS. 

The Most Adhesive Lubricator. 



Black lead, six pounds, are mixed with three 
pounds slaked lime ; eight pounds sulphate of baryta 
are mixed with seven pounds of linseed oil ; the 
whole mass is well mixed together to a uniform con- 
sistency, and the entire mass made more plastic. 
with the concentrated solution of silicate of soda. This 
cement may be used for numerous purposes, where 
hardness and adhesiveness are the desired objects, 
uniting at the same time steam and hot water. For 
locomotives, engines and machinery it is prepared 
from a mixture of soda liquid, at twenty-five degrees' 
B., added to a fine plumbago, talc, asbestos in equal 
quantities, so as to retain the thin plastic condition, 
and capable of dropping it on the journals in very 
small portions. 

The cheapest whitewash, which is very durable for 
indoor and outdoor work, is prepared by the follow- 
ing composition : To one pound slaked lime and 
one pound sulphate baryta, add one pint of silicate 
of soda and one pailful of hot water ; stir the mate- 
rials well together* and use it at once. If the color is 



SOLUBLE GLASS. 121 

intended for a yellow wash, add a quarter of a pound 
chrome yellow ; if for a blue wash, use instead of 
the latter a quarter of a pound ultramarine, and if 
the paint is intended to coat iron railing, stoves, 
steamboat chimneys, and to obtain a brown or black 
fire-proof paint, add half a pound of mangnanite, an 
oxide of manganese, or the pyrolusite, which is the 
black or gray peroxide of manganese. 

The Cheapest Silicate Paint for Barns and 
Outhouses. 

To one-half bushel of good lime add enough hot 
soluble glass of forty-two degrees B., and stir the 
whole well to a uniform liquid ; then add fifty pounds 
whiting, fifty pounds street dust and one gallon of 
soft soap. If the mass is too thick add enough raw 
linseed oil to dilute the whole composition. 

Luting for Gas Retorts. 

The soluble glass in fine powder, when mixed 
with four times a much powdered common 
white clay, all of which is made plastic with the 
liquid soluble glass of forty-two degrees B., is most 
suitable for luting gas pipes and gas retorts. It is 
the cheapest and most reliable cement. 

A New Cement with Silicate of Soda, 

which is said to be superior to hydraulic lime for 
uniting stone and resisting the action of the water. 



122 SOLUBLE GLASS. 

It becomes as hard as stone, is unchangeable by the 
air, and is proof against the action of acids. It is 
made by mixing together nineteen pounds sulphur 
and forty-two pounds pulverized stoneware and 
dry silicate of soda ; this mixture is exposed to a 
gentle heat, which melts the sulphur, and then the 
mass is stirred until it becomes thoroughly homo- 
genous, when it is run into molds and allowed to 
cool. It melts at about two hundred and forty-eight 
d egrees F. and may be re-employed without loss o 
any of its qualities, whenever it is desirable to change 
the form of an apparatus, by melting at a gentle 
heat, and operating as with asphalte. At two hun- 
dred and thirty degrees F. it becomes as hard as 
stone, and preserves its solidity in boiling water. 

Glazing of Pottery with Liquid Silicate. 

A mixture of soluble glass, felspar, kaolin and fluor- 
spar may be used to glaze bricks and pottery in 
a manner as perfect as the common lead-glazing, 
and much more safe in a sanitary point of view. 
When the ingredients are once mixed, they are 
ground in cylinders to a powder, which is passed 
through a very fine sieve. This powder, of which 
the natural color is white, but to which all tints can 
be given, is mixed with water in atub, till it presents 
nearly the consistency oi molding plaster. 

The brick or piece of pottery which is to be glazed 



SOLUBLE GLASS. 1 23 

is then plunged into the mixture. It adheres, 
on account of the porosity of the material, with 
which it incorporates while drying. Being placed 
in earthern forms, they are exposed in ovens to one 
thousand five hundred degrees Fahr. The heat melts 
the preparation, and the glazing spreads uniformly 
over the surface of the objects, which only have to 
be taken out of the oven to cool. 

Bricks treated in this way have great advantages. 
They are of an unusual strength, and resist as well 
the influences of the atmosphere as the action of the 
acids. They can successfully be employed to cover 
walls on the inside or outside, which they preserve 
completely from dampness. This new method of 
glazing may be made available for many industrial 
applications. 

Silicate Plastering 

which is claimed to prevent the sudden and disas- 
trous downfall of ceilings, so frequently occasioned 
by defects in the water pipes and consequent leakage 
or overflow. The invention consists of replacing the 
scratch coat and brown coat used in ordinary work 
by the combination of fibro-ligneous sheets with a 
cement composed of lime, sand, plaster and silicate 
of soda. The sheets are of a fabric resembling 
coarse bagging which is "secured to the lathing, and 
the cement is supplied in the ordinary way. A hard 
finish coating completes the work. 



124 soluble glass. 

S6luble Glass Application for Various Ce- 
ments. 

Porcelain, Glass and Metals are fastened together 
when broken, either by the liquid or gelatinous sili- 
cate by the following method : Heat the object to 
be fastened together to that of boiling water, and 
apply the soluble glass on both sides of the fracture, 
press them together and leave them in a warm place 
for a fortnight, when they will be fit for use. Fluor- 
spar finely ground, black oxide of manganese, oxide 
of iron (crocus,) finely powdered soluble glass, and 
many more refractory substances are suitable articles 
to mix with the liquid silica for the various cements 
in use ; a cement for fastening iron in stone, glass or 
wood is recommended, consisting in one part pre- 
pared chalk, one part marble dust, and made plastic 
with the liquid silica, or one part powdered soluble 
glass, two parts powdered fluorspar made into a 
paste with the liquid silica, and this is for pasting 
labels on glass bottles. 

Caseine or metamorphosed milk is also mixed with 
the liquid silica, and makes an excellent paste. 

Fireproof Cement is composed of the various 
oxides of iron, and formed into paste with the liquid 
silica. 

The Athens Marble Cement is composed of carbo- 
nate of lime, carbonate of magnesia and silica with 
oxide of iron, and made into a thin liquid and applied 
to the stone, which, on drying, is permanently fas- 



SOLUBLE GLASS. 1 25 

tened to the surface, and protects it from smoke, dust, 
and atmospheric agents. 

Common and fire brick acquire great strength if 
the silicate of soda has been employed in the manu- 
facture, and become indestructible. They are then 
particularly fit for baker ovens, wall and well foun- 
dations and furnace beds. 

Glazed paper for apothecaries' use, may likewise 
be prepared with the soluble glass. 

Metallic Cement is formed when a mixture of equal 
parts of oxide of zinc, per oxide of manganese and 
litharge, and made up with liquid silica, marble 
dust, and applied between the metals to be 
cemented. 

An Impermeable Cement Resisting Steam 

It is prepared by mixing six parts finely powdered 
blacklead, three parts slaked lime, and eight parts 
of plaster of Paris, made into consistency by the 
liquid silica. 

Zinc Cement for stopping cracks in metallic appa- 
ratus and other materials is made by mixing equal 
weights of zinc white and finely powdered soluble 
glass with a solution of chloride of zinc of the den- 
sity of one hundred and twenty-six ; it sets rapidly 
and resists the action of most agents. The simple 
mixture of oxide of zinc with a solution of the 
chloride of zinc, has also been recommended. 

Cement for any foundation wall is made by mixing 
one part of good slaked lime with three parts of fine 



126 SOLUBLE GLASS. 

sand, and three-quarters of its weight of finely pow- 
dered quick lime is added, and made into a paste 
with the liquid silica ; this mass becomes so hard in 
four days that a piece of sharp iron would not attack 
it. 

The Gypsum and Clay Cement. 

This cement is very hard, and is prepared by an 
intimate mixture with liquid silica, after the gypsum 
has been calcined, and it is preferred to lime cement 
for the reason that by the action of fire, it becomes 
reconverted into lime, which, when the waters from 
fire engines is brought to bear upon it, expands much 
and forces out the walls to the destruction of the 
walls. 

Hard Adhesive Cement. 

It consists in making five parts powdered clay, 
two parts iron filings, one part of black oxide 
of manganese, and one-half part of borax made 
into paste with liquid silica ; when dry is very hard, 
and withstands water. Also a mixture of manganese 
and zinc white, with plaster of Paris, forms a very 
hard cement, and has great adhesive capacity. 

Drain and Gaspipcs for conducting to sewers and 
houses, may be made as permanent as iron pipes by 
using a hard cement consisting of hydraulic lime, 
clay and sand, mixed with fine powdered alum and 
soluble glass, all made plastic by the liquid silica. 



SOLUBLE GLASS. 1 27 

This mass when dry and burnt, will resist a pressure 
of six hundred pounds to the square inch, while iron 
pipes burst under a pressure of four hundred pounds 
to the square inch. 

Cement for Closing Cracks in Stoves, &c. 

A useful cement for closing up cracks in stove 
plates, stove doors, etc., is prepared by mixing finely 
pulverized iron, such as can be procured at the drug- 
gists, with liquid water glass, to a thick paste, and 
then coating the cracks with it. The hotter the fire 
the sooner does the cement melt with its metallic 
ingredients, and the more completely will the crack 
become closed. 

Cement for a Cistern. 

Take 19 parts of Plaster of Paris. 
" 2 " Salt Cake. 

" 4 " Clay. 

11 4 " Slaked Lime, 

Made into a plastic cement with the liquid silicate of 
soda, and before it hardens, add liquid chloride of 
calcium. 

For sweetening the water in cisterns, which is found 
to be hard ; may be made soft by one gallon of silicate 
of soda in the cistern, and repeat the operation once 
a month. 

The best iron cement is composed of calcined plas- 
ter and iron filings, from each ten parts, four parts 



128 . SOLUBLE GLASS. 

oxide manganese, two parts slaked lime, made plas- 
tic with the liquid silicate of soda. 

The most refractory cement is formed from silica, 
plumbago, and soapstone. These materials mixed 
in certain proportions and made plastic by the liquid 
silica, form a most valuable cement for locomotive 
journals and other lubricating purposes, for lining of 
steam boilers as well as coating, and for filling up air- 
holes in iron castings. By the addition of peroxide 
of manganese, it may be much improved, and serve 
as a permanent paint, which is fire and waterproof. 

Besides the cements, such as the Portland, Roman, 
Keene's, Parian and Martin's, and those obtained from 
the Puzzuolanas and Trass, as obtained near Naples, 
and from the extinct volcanic districts, such as 
Vivarais in Central France, at Brihl, near Andernach 
on the Rhine, and also near Edinburgh in Scotland, 
and the Rosendale, all of which, when mixed with 
coal cinders, slags and scoria and wood ashes, con- 
tain more or less soluble alkali, and have a consider- 
able effect in hastening the absorption of the mois- 
ture, and facilitating the setting of the lime and 
sand. There are also the burnt clays or terra 
cottk, which are frequently used as artificial 
stone, but from their great and unequal contrac- 
tion, and the facility with which they are acted 
on by frost, are rarely satisfactory, except treated 
with "soluble glass as has been destroyed. 

There are also many varieties of concrete now 
manufactured in vast blocks and a perfectly solid 
mass, which replace now the accumulations of rub- 



SOLUBLE GLASS. 1 29 

bish and loosely aggregated stones, once thought 
sufficient for filling up intervals between walls of 
solid masonry, especially in piers, harbors, and other 
important works, and to which the name concrete 
has been given, and means a species of rough mason- 
ry, consistency of gravel or broken stone mixed with 
lime, the latter being slaked and immediately put in 
contact with the gravel. When lime is used that 
has previously been worked into a paste, it passes 
by the name of Beton, and the BetonCoignet Build- 
ing has of late been introduced into this country, 
and to a great extent substituted for brick and stone. 

The Soluble Glass as a Substitute for Glue. 

It has proven quite useful in applying the liquid 
glass for glueing wood and paper together, instead 
of the common glue, and it is sold in the trade as 
mucilage, and is applied on paste board instead of 
emery or corundum paper, used by cabinet makers 
and other mechanics for polishing. As a paste for 
book-binders instead of glue, starch or dexterine, it 
has also proved quite useful. Earthenware may be 
kept more durable by lining them with a weak solution. 
It is likewise used on leather, provided the same is 
not exposed to too much bending. 

For the glazing or enamelling of culinary vessels* 
made either from iron or stone ware, the soluble 
glass is usefully applied in the following manner : 

The silicate solution of soda and potash is mixed 
with thick lime water ; to one hundred parts of the 



130 SOLUBLE GLASS. 

silicate add one part of lime water, made from one 
part caustic lime to six parts of water. The mixture 
is then evaporated to dryness and reduced to fine 
powder. By dipping first the objects to be glazed 
in the liquid silica, the powder is then sifted over 
them ; when dry, the operation is repeated again 
the coating becomes so hard that it cannot be rubbed 
off by the hands ; they are then treated like other 
ware by putting them into a furnace, requiring, how- 
ever, not a very great heat. 

A similar process is to prepare a mass from one 
hundred parts powdered quartz, eighty parts pure 
potash, ten parts saltpetre, and twenty parts slaked 
lime, which mixture is made into a thin paste with 
the liquid silicate, and then burnt. This glazing is 
very durable and resists both vegetable and mineral 
acids like common glass. It requires no great skill 
to execute the operation, and the expense to prepare 
such a glazing is but a trifle. 

The Soluble Glass in Calico Printing. _ 

Soluble glass is largely used for discharging certain 
colors, and to make the cloth susceptible of receiving 
other vegetable tints and colors, by means of plung- 
ing it into a solution of the silicate of soda, either 
simply or combined with arsenic or arsenite of soda. 
It is known under the name of dunging salt, and 
was formerly replaced by an article called " nihilum 
album " or excrements from do^s. 



soluble glass. i 3 i 

Silica Paint for Protecting Ship Bottoms. 

There are two paints recommended for this pur- 
pose : 



No, 


1, Red Lead 


100 1 


pounds. 


No. 


2, Red Lead 120 pounds. 




White Lead 


60 


" 




Oxide Zinc 60 " 




Litharge 


20 


" 




Yellow Ochre 20 " 




Oxide Zinc 


40 


" 




Chloride Zinc 60 " 




Linseed Oil 


3 


gallons, 




Linseed Oil 3 gallons, 




Soluble Glass 


3 


<4 




Soluble Glass 3 l< 



Two or three coats may be applied. 

The Most Durable Aquarium Cement. 

The materials of a water-resisting composition 
are prepared by mixing finely powdered dry silicate 
of soda, powdered chalk, porus alum, and fine sand in 
equal quantities, made plastic with the liquid silicate, 
and applied at the joints, and worked over with fluid 
chloride of calcium, and when quite dry let some 
weak hydrofluoric acid pass over the cemented joints. 
This cement will be permanently impervious to 
water, and will not crack. The same composition is 
quite suitable for breweries, malt houses, linings for 
water tanks, and cellars into which water flows. 

The author considers it advisable to show, also, 
the advantages of concrete, by the description of the 
concrete bridge at London, and will state, that the 
addition of silicate of soda to the concrete will 
undoubtedly ensure a great saving. 

The material consists of one part of Portland 
cement to eight parts of coarse gravel. The cement 



132 SOLUBLE GLASS. 

and gravel are first well mixed together in a dry 
state, and when this is done it is damped by means 
of a large watering pot, containing some hot silicate 
of soda, and again mixed by a prolonged drag, such 
as is used for dragging dung out of the cart, until 
the entire heap has been wetted and mixed together. 
It is then put in iron or zinc pails and pored into the 
frame, where, it is levelled by men stationed for the 
purpose. In order to save concrete, large lumps of 
stones or brickbats are put into the centre of the 
wall, and covered over and about with concrete. 
Frost does not affect the concrete after it has once 
set, which, with good cement, will be in about five 
or six hours. Nor do heavy rains appear to injure it 
in the slightest degree, though they may chance to 
fall ere the concrete has hardened. The walls can be 
made straight and even as it is possible for walls to 
to be, and the corners as sharp and neat as if they 
had been formed of the most carefully dressed stone. 

The Soluble Glass as Manure for- Grapevines 
and Cereals. 

By putting the dry silicate of soda at the roots of 
grapevines, etc., with or without the addition of phos- 
phate of lime, has, by experiments, proved of immense 
benefit to the growth of the plant, whehe applied, to 
a proper thickness, and tends to increase the size and 
yield of the vegetable. 



• SOLUBLE GLASS. 1 33 

A Strong Cement for Iron. 

To four or five parts clay, dry and powdered, two 
parts iron filings, one part manganese, one-half part 
borax, in a paste made with soluble glass, or equal 
parts zinc white and manganese, made to a paste. 
Must be used immediately. 

Iron Cement for Water and Gas Pipes and 

Castings, 

It is obtained from sixty parts cast iron turnings, 
mixed with two parts of sal ammonia, one part flour 
sulphur, and one part lime cement ; the whole made 
plastic by the liquid glass just before using it. To 
mend holes of wdiatever description in iron castings, 
it is unequalled. It becomes soon very hard, and 
every crevice is filled. 

Colored Cements. 

To a solution of silicate of sod^i of one thousand 
two hundred and ninety-eight, spec, grav., add, 
while stirring first pulverized and previously washed 
lixiviated chalk, so as to forrn a thick mass, to which 
are added, for coloring purposes, the following sub- 
stances : 

For black, sulphuret of antimony. 

Gray, iron filings. 

Gray w r hite, zinc dust. 

Bright green, carbonate of copper. 



134 



SOLUBLE GLASS. 



Blue, orange and red. Cobalt, vermilion and car- 
mine. 

This cement hardens in six to eight hours, and 
bears polishing like marble. 

Coating for Outside Walls. 



Th following coating for rough brick walls is used 
by the United States Government for painting light- 
houses, and effectually prevents moisture from strik- 
ing thorough : Take of fresh Rosendale cement 
three parts, and of clean, fine sand one part ; mix 
with soluble glass thoroughly. This gives a gray or 
granite color, dark or light, according to the color 
of the cement. If brick color is desired, add enough 
Venetian red to the mixture to produce the color. 
If a very light color is desired, lime may be 
used with the cement and sand. Care must be 
taken to have all the ingredients well mixed 
together. In applying the wash, the wall must be 
wet with clean fresh water ; then follow immediately 
with the cement wash. This prevents the bricks 
from absorbing the water from the wash too rapidly, 
and gives time for the cement to set. The wash 
must be well stirred during the application. The 
mixture is to be made as thick as can be applied con- 
veniently with a whitewash brush. It is admirably 
suited for brickwork, fences, etc., but it cannot be 
used to advantage over paint or whitewash. 



soluble glass. i 35 

Preservation of Stones from Green Coating. 

The decay of granite, marble, limestones, sand- 
stones, and all natural building stones, is the com- 
bined effect of various causes, and among these is a 
very minute lichen, the Lepra antiquitalis, which is 
one of the worst enemies of stone, and its action is 
to such an extent that, for instance, the beautiful 
marble sculptures of the well-known Pare de Ver- 
sailles will, unless proper measures are taken for stay- 
ing the process of decay, be unsightly and ugly 
masses of dirt, and quite irretrievably lost, as works 
of art, within the next fifty years. Various places 
and instances are cited of the application of oxide of 
copper and its salts, and the application of soluble 
glass, in which white arsenic is dissolved, or, as it is 
called, liquid arsenical silicate ; and the length 
of time which has elapsed since such application, 
seems to warrant the conclusion that these 
compounds act as preservatives of stone. In 
reference to granite, the author states that this 
stone is also, according to the experience of Egyp- 
tian engineers, far more readily affected by a 
moist climate than one would be let to believe. 
The obelisk of Luxur, brought from Upper Egypt to 
Paris, has become blanched and full of small cracks 
during the forty years it has stood on the Place de 
la Concorde ; although forty centuries had not per- 
ceptibly affected it as long as it was in Egypt. 
Granite in a moist climate becomes the seat of a 
minute cryptogamic plant, which greatly aids its 



i%6 



SOLUBLE GLASS. 



destruction ; and it is, moreover, a well-known fact, 
that the disintegration of this stone, which is com- 
posed of three separate minerals, (quartz, mica, and 
felspar), depends very greatly upon the thorough 
and intimate mixture, as well as the chemical com- 
position, of these three ingredients, each of which, 
in a separate state, more easily withstands the influ- 
ence of the weather. 

The most refractory cement is formed from silica, 
asbestos, plumbago and soap stone. These materials, 
mixed in certain proportions and made plastic by 
the liquid silica, form a most valuable cement for 
locomotive journals and other lubricating purposes, 
for lining of steam boilers as well as coating, for 
filling up airholes in iron castings. By the addition 
of peroxide of manganese, it may be much improved, 
and serve as a permanent paint, which is fire and 
water proof. 

Beton Building. 



Of all the compositions which in late days have 
been introduced as a substitute for brick or stone- 
work, there is not one that presents more attrac- 
tions as a material then beton. But the use of it is 
limited to those localities where water-lime can be 
had at a reasonable price. For, although that 
admirable cement is about the only one of its com- 
ponent parts that is expensive, yet the proportion 
used makes the beton more costly than could be 
wished, notwithstanding its many merits as a build- 



SOLUBLE GLASS. 1 37 

ing material. There need not be any stone or stone 
chips used in the* making of beton. All that is 
required to make a quick-setting and very durable 
material is, sand, three parts water-lime, one part ; 
broken brick, six parts. The water-lime and sand 
should be well mixed together, dry. Then have as 
much water thrown on as will make a moderately 
stiff mass, when it is to be instantly transferred to 
the moulds, which are already in their positions on 
the walls, and the centre to be packed with the 
broken brick, which, being very porous, will receive 
the moist cement readily on its broken faces, and 
help to set the whole. The mode of proceeding to 
construct the courses is by means of moulds easily 
adjusted and taken apart. They are to be calcu- 
lated so as to inclose a block of beton of the required 
thickness of the wall, and of, say, half again that 
thickness in length. Their height may be ten 
inches. Thus, if the wall be twelve inches, the block 
will be the same, and also eighteen inches long by 
ten inches high. 



SOAPS. 

Silicate of Soda in Soap Making. 

DIRECTIONS. — In the use of silicate of soda in 
properly made soap, it is absolutely necessary that 
all soaps, settled or curd, must be made according to 



138 



SOLUBLE GLASS. 



the experience of the most practical soap boilers, 
which is that the soap shall be perfectly neutral, o;r 
a chemical stearate of soda. In other words, soaps 
are chemically considered the compounds of the fatty 
acids with the bases, and the results are that soap 
proves the detergent material formed by saponifying 
fat with alkalies, and its theory is that the alkali dis- 
places the natural base of the fat which remains in 
solution, and unites with the eliminated acids ; the 
compounds so formed differ in consistence with that 
of the grease and with the nature of the alkali em- 
ployed ; potash yields soft, and soda hard soaps. A 
true and good soap must be a definite, chemical com- 
pound. Rosin and silicate of soda may be added as an 
ameliorator, provided they are added in moderate 
quantities. — They both possess cleansing qualities. 

It is only since 1813 that any definite idea was 
formed of the composition of the various fats and 
oils from which soaps are made, and the process 
which was in use for centuries, before anything was 
known of the principles upon which it was based, 
were only empirical. The conditions are : 

First, The proper temperature, and, 
* Second, The mode of crutching them in the chemi- 
cally formed soap. 

The idea formerly entertained that silicate of soda 
is an adulteration, and without possessing any deter- 
gent properties, has long been exploded ; for silicate 
of soda, by itself, has been in use in the public insti- 
tutions of Germany and England for washing clothes, 
and cleansing yarns and w T ool in the manufactories, 



SOLUBLE GLASS. 1 39 

for thirty years. During our civil war, when rosin 
rose to a very high price, the soap manufacturers 
resorted to the employment of silicate of Soda, and 
it has ever since retained its prestige. 

The application of silicate can only be made when 
the soap and silicate are in a neutral condition, for if 
there is the least trace of a fatty acid, the silica will 
separate from the soda, which, after a short time 
will effloresce and make the soap unsightly. 

The fatty matters employed by the soap makers 
are chiefly tallow, palm oil, cocoanut oil, and grease, 
all intended for hard soaps ; and all fatty oils, seal 
and whale oils for soft soap. In the manufacture of 
a hard wash soap, the soapboilers use to one hundred 
potmds of tallow, sixty pounds caustic soda, ot 
thirty-three degrees to thirty-one degrees B., ten 
pounds cocoanut oil, and ten pounds liquid silicate of 
soda L. In this process the silicate may be 
thoroughly mixed with the caustic soda. 

For settled soap with the addition of rosin, it is 
easy to add twenty-five per cent, silicate liquid or 
syrup which is crutched in, and at the same tempera- 
ture with the soap. 

For common brown soap, seventy-five per cent, of 
silicate may be used. 

The boiled down soap, called curd soap, may con- 
tain one hundred pounds rosin to one hundred 
pounds tallow, and also an addition of eighty pounds 
silicate L. Also twenty-five to one hundred pounds 
of silicate, with each one hundred pounds of settled 
soap in the frame, or in a crutching box first, and 



140 



SOLUBLE GLASS. 



then framed as follows : Take the hot soap from the 
nigar at one hundred and fifty degrees F. and mix it 
with any quantity you may desire of hot, clear pre- 
pared silicate, at about one hundred and thirty 
degrees F., or in other like proportion of heat in 
each ; crutch these two articles well together, adding 
about three pounds of aqua ammonia to each batch 
of one thousand pounds. 

For cold soap, which makes a good lather and 
keeps without shrinking any length of time, make 
a mixture of one gallon of liquid silicate at about 
thirty-five degrees B., with one and a half gallons of 
lye of about twenty-four degrees B., and crutch that 
together, with about ten pounds of hot grease or 
tallow at about one hundred degrees F., or in larger 
quantities in same proportions until it becomes stiff 
and cold. 

Silex, china clay, whitening, Paris white, terra 
alba or talc, may be used in mixing with hot or cold 
soap, by making a paste with either article with the 
liquid silicate, and then crutching it with the soap. 
No more than twenty-five per cent, oi either of the 
above articles ought to be used. 

Calcined and powdered sulphate of soda will com- 
bine with the silicate and prevent the efflorescence. 

The Silicate of Soda in Common or House- 
hold Soaps. — Hard Soaps. 



Hard soaps rre always soda soaps. There are 
boiled soaps in the trade as well as soaps made in 



SOLUBLE GLASS. 141 

the cold way. We can technically distinguish 
among the hard soaps thus, grained soaps, i. e., those 
in which a separation of the under-lye has been 
made, and filled soaps, i. e., those in which the whole 
contents of the boiling-pan are kept together and 
sold as soap. The cocoanut oil especially, is em- 
ployed for the manufacture of filled soaps, because 
it is easily soluble in brine, requiring a very large 
quantity to separate them, and then they become so 
hard that they can scarcely be cut with a knife 
The more solid constituents a fat contains, the harder 
the soap produced ; the more oleine, however, the 
softer the soap. In mixing the fats in different pro- 
portions, we are therefore enabled to produce soaps 
of any consistency. But this also depends upon the 
strength of the lye used in the process. Weak and 
middling strong lyes will produce a light soap, while 
lies of twenty-five to thirty degrees B., will produce 
a soap heavier than water. Sometimes a small 
admixture of sulphate of soda is employed in making 
soap, for the special purpose of preventing too great 
solubility of it when used in washing. A soap not 
containing more than one per cent, of this substance, 
is very well adapted for washing. 

In the manufacture of soaps, one-third or one- 
fourth of lat is frequently substituted by rosin. Such 
soaps are called rosin soaps. For the transformation 
of one hundred pounds of fat into soap, there are 
generally necessary twelve and a half pounds of 
solid caustic soda. It is, however, obvious that this 
quantity must be more or less in proportion to the 



1.42 



SOLUBLE GLASS. 



nature of the fat. We will, upon this basis,, presently' 
show how to calculate the quantity of lye of a cer- 
tain degree necessary for transforming a certain 
weight of fat into soap. Suppose we wish to 
saponify four hundred pounds of fat, how much lye 
of twelve deg. Baume will be requisite ? This lye is 
of a specific gravity of I.c8 ; one gallon of it weighs 
1.08x8.3=8.9 pounds (one gallon of water has the 
weight of eight and three tenths pounds), or the 
weight of ten gallons of lye of twelve deg. B., equal 
eighty-nine pounds. These contain 7.69 per cent. 
of caustic soda ; ten gallons will contain 6.84 pounds 
of caustic soda. Now 6.84 pounds is one-seventh 
of the quantity for transforming four hundred pounds 
of fat into soap ; hence 7x10=70 gallons must be 
employed, provided the lye be perfectly caustic and 
free of foreign salts. 

We now give a short description of the process 
for manufacturing the different kinds of soap. 



1. Tallow Soaps, 



The following soaps may contain twenty-five 
per cent, of liquid soluble glass of forty-two deg. B. ; 

These are the most important, owing to the 
cheapness of the fat employed, and their introduc- 
tion almost everywhere, But as so many methods 
for making this kind of soap exist, we will confine 
ourselves to a description of a process generally 
adopted in France, the country unrivalled for the 
cheapness and goodness of soaps. 



SOLUBLE GLASS. 143 

Suppose we wish to saponify one thousand pounds 
of fat. We commence by putting the tallow into the 
boiler, and melt it over a slow heat. This done, we 
add seventy to eighty gallons of lye often to twelve 
deg. B., stir well and keep a gentle fire for several 
hours. Should part of the fat separate from the 
mass, which is often the case, an oily liquid will be 
observed floating on the top. We must then add, 
gradually, thirty-five to forty gallons of lye of fifteen 
to eighteen deg, B. By this addition, the whole 
contents will soon form a homogeneous mass of a 
grayish-white color. In order to establish the 
necessary consistency to the paste, we must keep 
gently boiling for several hours, adding every hour 
six to seven gallons of lye of twenty deg. B. 

The time necessary for the first operation is from 
ten to twelve hours for one thousand pounds of fat. 
After this we pass to the cutting process, and oper- 
ate exactly as described above. It is absolutely 
essential that care be taken to stir the ingredients 
well while adding the salt. When the separation 
has taken place, we should leave it altogether quiet 
tor several hours, and then draw off the colored 
under-lye ; ninety gallons of lye of twenty-five 
deg. should be added ; and we may also increase the 
heat, there being strong lye at the bottom of the 
pan which preserves the soap from burning. We 
then boil this mass from ten to twelve hours, adding 
every hour five gallons of lye of twenty-five deg. 
Four or five hours' boiling, however, w 7 ill often be 
sufficient to saturate the soap. This .be 



144 SOLUBLE GLASS. 

plished, we should extinguish the fire, leave it quiet 
for an hour, and then draw off the under-lye. It 
will measure from twenty-five to thirty deg. B. To 
complete the process, we must add about fifty gal- 
lons of lye of four deg. B. This is suffered to boil 
gently for one and a half to two hours, stirring from 
time to time with the crutch, and finally extinguish- 
ing the fire and covering the pan. The soap will 
thus separate from the lye, and rise to the top. 
After five to six hours, while yet in a liquid state, 
we should pour it into the frames, taking due care 
that no lye be mixed with it. In the frames, it 
should be well crutched and stirred for some time. 
For neutralizing the disagreeable tallow odor, one to 
two ounces of a well-scented essential oil should be 
added to one hundred pounds of the soap, and after 
seven or eight days it may be cut. One hundred 
pounds of tallow will yield one hundred and sixty- 
five to one hundred and seventy pounds of soap. 

2. Tallow Rosin Soaps with Thirty per Cent, 
of Soluble Glass. 

Rosin, when incorporated with a soap, to a certain 
amount, will make it more soluble and detersive. 
The lighter the rosin, the more it is valued ; 
fifteen per cent, of rosin with eighty-five per cent, of 
tallow answers a good purpose, but beyond that 
limit the soap is depreciated in color, in firmness, 
and quality. Even for the cheapest grade, the 
quantity of rosin should not exceed thirty-three per 



SOLUBLE GLASS. 145 

cent., for otherwise the soap will be clammy, soft, 
and unprofitable to the consumer. The rosin like 
fats can be saponified with alkali ; twelve gallons of 
lye of thirty deg. B., are needed for every one hun- 
dred pounds of rosin. Some soapmakers melt it 
with the fat in the commencement of the boiling for 
soap, but this method is not recommendable, as 
experience has proven that a much better product is 
obtained by first producing a tallow soap, and after- 
wards mixing the rosin soap with it, made in the 
meantime in a special kettle. Both mixtures (soaps) 
have to be stirred and beaten thoroughly for half an 
hour, and the whole passed through a sieve before 
they are filled into the frames, and therein well 
stirred and crutched. Some palm oil, when saponi- 
fied with the tallow, will very much improve the 
appearance of the soap. 

We will here briefly describe the preparation of 

The Rosin Soap with Twenty-five Per Cent. 
Soluble Glass Liquid. 

If eighty gallons of lye be put into a kettle of 
sufficient capacity, we should first boil the contents 
and then throw rosin in at intervals of five or six 
minutes, and in portions of fifteen to twenty pounds, 
until one thousand three hundred and twenty 
pounds have been added. The rosin must be previ- 
ously well pulverized, and while one workman is 
occupied with throwing it in, another should be con- 
stantly engaged in stirring it, as the mixture easily 



146 SOLUBLE GLASS. 

ascends. The heat must not be too rapidly increased, 

nor is it necessary that it should boil all the time, 
but simply keep the temperature near the boiling; 
point. It is, however, absolutely requisite to keep 
stirring the paste all the time, otherwise agglomera- 
tions of rosin w r ill be formed. Saponification will be 
finished in two hours, and then the mixture, with 
the fat, is converted into soap as above described. 

3. Cocoanut Oil Soap with Twenty Per Cent. 
Soluble Glass Liquid. 

The cocoanut oil, as often mentioned, acts differ- 
ently from any other fats, in combination with which 
weak lyes produce a milky mixture. Such lyes, 
however, have no effect upon cocoanut oil, for it can 
be seen floating on the top, whilst strong lyes of 
twenty-five to thirty degrees very soon produce 
saponification throughout the whole mass. 

Soapmakers generally use a lye of twenty-seven 
deg., cold weighed, which will saponify an equal 
weight of cocoanut oil, one hundred pounds, for 
instance, making nearly tw r o hundred pounds of soap. 
The process is very simple. The oil is put in the 
pan together with the lye, and then heat is applied. 
After continually stirring it for one or tw T o hours, the 
paste will be seen gradually thickening, when the 
temperature of the heat applied should be moder- 
ated, but the stirring continued. After a while the 
paste becomes transformed into a white semi-solid 
mass, which forms the soap, and this has to be filled 



SOLUBLE GLASS. 1 47 

immediately into the frames, because solidification 
takes place very quickly. 

Often a mixture is used of equal parts of tallow 
and cocoanut oil, or of bleached palm oil and cocoa- 
nut oil, which yields a very fine soap. Ninety to 
ninety-five per cent, of cocoanut oil, with five to ten 
per cent, of natural palm oil, yields, also, a nice 
soap* and all these fats, when mixed with cocoanut 
oil, in not too large proportions, will be as easily 
saponified as if the latter alone were used. Soap- 
makers, we may here remark, seldom, if ever, 
attempt to separate cocoanut oil with brine. 

4. Palm Oil Soaps and Addition of Twenty 
Per Cent. Silicate. 

Palm oil is rarely used exclusively as a soap stock, 
but generally employed with an admixture of rosin, 
and it then yields the yellow soap ; for white soap, 
however, these are employed in the bleached state. 
For some kinds of soap, palm oil is saponified with 
five to ten per cent, of cocoanut oil ; more is often 
used of the latter, and then filled soaps are obtained. 
Demi-palm is a soap consisting of equal parts of tal- 
low and palm butter, to which is added a very sm?ll 
quantity of rosin and cocoanut butter. 



148 



SOLUBLE GLASS. 



The following are receipts for admixtures : 

Palm oil, , . ,. . . 300 lbs. 

Tallow, 200 " 

Rosin, . . . . . , 20 " 

Silicate, . . . , , , . 50 " 

Palm oil may be made into soap exactly in the 
same way as tallow. If rosin be incorporated, it is 
better to produce first the combination of the rosin 
with the lye, and mix the same with the finished 
palm oil soap. 

The soap made of the bleached palm oil is of a 
perfect whiteness, and so far as coloring is concerned 
can scarcely be distinguished from tallow. Palm soap 
becomes bleached when exposed to the light. 

Different Soaps, 



which may contain from twenty to fifty per cent, of 
the liquid soluble glass of forty-four degrees B. 

Such are the red oil soap, elaidin, and the si Heated. 
Red oil is not generally saponified by itself, but 
becomes so when combined with tallow or hog's fat. 
Six hundred pounds of red oil and four hundred 
pounds of an animal fat, together with strong lye, 
say of twenty-five to twenty-eight deg. B., make a 
good soap. Red oil is easier made into soap than 
elaidin, which is the product of the action of nitrous 
acid upon oleic acid. Elaidin is like tallow, solid 
and hard, and gives a soap superior to the best tal- 
low soap. It can be made into grain as well as into 



SOLUBLE GLASS. 1 49 

filled soap, and we may mention here that the union, 
of the red oil or oleic acid with alkalies or the com- 
bination of its derivate, the elaidic acid, with alkali, 
or union of the rosin with soda or potash, is not a 
saponification, properly speaking, because chemically 
there is no formation of glycerine ; but we may, 
nevertheless, use this term for expressing the process 
of combination. 

Silicated soaps are seldom met with in trade, 
owing, in a great measure, to the fact that the 
method of preparing them requires large percentages 
of soluble glass, and another, because their prepa- 
ration was not understood. It may be stated that 
the fat soap in which the soluble glass is stirred 
must be of a perfect neutrality, ior if there be 
the least trace of a fatty acid, silica will be pre- 
cipitated and afterwards soda will effloresce. Not 
more than twenty per cent, of soluble glass (marking 
thirty-five deg. B.) should ever be taken. 

Various Soft Soaps Which Contain Fifty Per 
Cent. Silicate. 

The difference between soda and potash soaps 
consists in this — the first are hard, but the latter are 
soft. The former can therefore be purified by several 
operations, and brought to a water amount of a 
certain limit, while the latter keep the smeary form, 
and are brought in commerce with ?\\ their impuri- 
ties, and the whole amount of water they can hold. 
If it be asked what advantage a soft or potash soap 



150 SOLUBLE GLASS. 

offers, we are told that it is easier soluble than soda 
soap, and also cheaper. With the first point we 
must agree, though it is easy enough to make a 
solution of soda soap, provided we heat it, but not 
so with the latter. It is certainly not cheaper than 
soda soap, as we will show hereafter. 

The equivalent of caustic soda is forty, that of the 
potassa fifty-six ; i. e., we must have forty parts of 
soda for transforming a certain quantity of fat into 
soap, while we need fifty-six parts of potash for doing 
the same. Now as the price of the potash is at least 
twice as much as that of the caustic soda, it follows 
that we spend about three and a half times as much 
by employing potash as we would do by using soda. 

For the manufacture of soft soaps, hempseed oil, 
linseed oil, poppy oil, rapeseed, colza, whale, and 
seal oils are used. 

Saponification is commenced with a lye of nine to 
eleven deg. B., and the contents of the kettle kept 
boiling until the paste becomes of sufficient consis- 
tency to draw threads, as it were, out of a streaky 
substance. It then undergoes the process of clear 
boiling, for which purpose a lye of twenty-five deg. 
B., should be used. Stirring must be done all the 
time, but when the paste does not sink any more 
(first it ascends), boils quietly, and shows the forma- 
tion of scales, it may be considered complete. The 
barrels should be immediately filled, in which it is to 
be offered to the trade. The quality of the soft 
soaps is estimated according to their consistency. 
Consistent soaps are preferable to inconsistent ones. 



SOLUBLE GLASS. I 5 I 

Green soap was formerly made of hempseed oil. It 
is now, however, made principally of whale oils, but 
as they have a yellow color, and consumers are 
accustomed to the green color of the hempseed oil, 
soap manufacturers mix the soaps made of the w T hale 
oils with finely powdered indigo, or the indigo- 
sulphate of lime, which is prepared by dissolving 
indigo in sulphuric acid, diluting it w r ith water, and 
saturating the whole with lime-milk. 

The black soft soap is made by adding to the soap 
a mixture of a solution of copperas and logwood or 
gall-nuts. 

Silicate Washing Fluid. 

To one gallon concentrated liquid soluble glass of 
forty-four deg. B., add one pound of caustic ammo- 
nia and one-half pound caustic lye. This fluid will 
wash five hundred pieces. 

SlLICO-TUNGSTATE OF SODA, 

for protecting -textile fabrics and timber. By adding 
to one gallon silicate of soda of forty-four deg. B., 
one-half gallon solution of tungstate of soda, (con- 
taining one-half pound of the dry salt), and dipping 
the dresses, clothes, etc., in the liquid but once, will 
protect the goods from inflammation. 

The timber, lumber, or other building materials 
may be protected with the above solution, by adding 
either chloride of calcium or porous alum, say one 



152 



SOLUBLE GLASS. 



pound of either to one-half gallon of water, and 
dip the materials first treated with the silico- 
tungstate of soda, into the solution of the latter, 
soon after the first treatment, just before the infil- 
tered liquid has become dry. 



Estimation of the Substances with Which a 
Soap may be Adulterated. 



Water. 



; Earthy Matters and Salts. Soluble and In- 
soluble in Water. 



Soluble. 
.Chloride of Sodium. 
I Soda. 

i Glauber Salt. 
(Borax. 

; Soluble Glass. 
| Carbonate of Ammonia. 
I Alum. 
Acetate of Lead. 



Insoluble. 



Soluble in Hydro- 
chloric Acid. 

MAGNESIA. 

LIME. 

CHALK, OR MIN- 
ERAL WHITE. 

BONE ASHES. 

PIPE CLAY. 

Not soluble in Hy- 
drochloric Arid. 

SULPHATE OF 
BARYTA. 

SAND,orSILEX.* 



Soluble and Insoluble 
in Water. 



Soluble. 
Sugar. 
Starch, f 
Dexterin. 
Glue. 



Insoluble 
Free Rosin. 
Free Fat. 



* An admixture of sand cannot be regarded as fraud if the soap is sold as 
sand or pumice soap. 

t We do not know if starch has any cleansing qualities; it is so stated in a 
report on different uses of the potato, published in 1827, by the two French 
chemists, Payen and Chevalier, but we doubt it. 



SOLUBLE GLASS. 



TABLE FOR CONVERTING THE AREOMETRIC DE 

GREES OF BAUME INTO THE SPECIFIC WEIGHTS 

OF LIQUIDS HEAVIER THAN WATER. 

Temperature of liquid, 54 ° Fahr. 






1 .0000 


1 18 


1. 1343 i 


36 


1 . 3003 


54 


1. 55io 


I 


1.0066 


*9 


1,1408 


37 


1.3217 


54 


1.6471 


2 


1.OT33 i 


! 20 


1.1585 


38 


1.3333 


56 


1.6667 


3 


1. 0201 


! 2I 


1. 1603 | 


39 


I-345I 


% 


1.6868 


4 


I.0270 


22 


T.1692 


40 


I.357I I 


1.7074 


5 


1.0340 


23 


1,1783 


4i 


1-3694 | 


59 


1.7285 


6 


1. 0401 


24 


1.1875 | 


42 


1.3818 | 


60 


1.7501 


7 


I.0483 | 


25 


1. 1908 1 


43 


1.3845 | 


6! I 


1.7722 


S 


1.0556 J 


26 


1.2063 ; 


44 


1.4094 i 


62 


I.7950 


9 


I.0630 ! 


27 


1. 2160 i 


45 


1.4206 


63 


1. 8184 


10 


I.0704 j 


28 


1.2258 


46 


1-4339 


64 


1.8423 


11 


1.0780 ! 


29 


1.2358 


47 


1.4476 


65 


1.8669 


12 


r.0857 


30 


1.2459 


48 


14615 


66 


1.8922 


13 


1.0935 


31 


1.2562 


49 


1.4758 


67 


1. 9180 


14 


1.0994 ! 


32 


1.2667 1 


50 


1.4902 


68 


1.9447 


15 


1. 1095 


33 


L2773 ! 


5i 


1.4951 


69 


1.9721 


16 


1.1176 


34 


I.288I ! 


52 


1.5200 ! 


70 


2.0003 


17 


1. 1259 | 


35 


1.2992 : 


53 


1.5353 ! 







TABLE FOR THE QUANTITY OF CAUSTIC SODA IN 
SODA LYE. 





CD 


I 

►i 'O 


hi 

CD 




» 




p O 




p CD 




P CD 




p CD 


< O 




< O 




<< 




< O 




CD 




CD 




CD 




e* a> 


fcj 


5-fci> 


ts 


S-Sb 


fcj 


eft* 


H 


<rH 


V} 




*< 


ct- 


*< O 


.4285 


30.220 


I.3I98 


22.363 


1.2392 


15. IIC 


1. 1042 


.4193 


29.6l6 


I.3T43 


21.884 


1.2280 


14,506 


I.O948 


.4101 


29.0II 


I.3I25 


21.894 


1. 2178 


13.901 


1.0855 


.4011 


28.407 


JI.3O53 


21.154 


1.2058 


13.297 


I.O764 


3923 


27.802 


!l,2982 


20,550 


LI948 


12.692 


I.0675 


.3836 


27.200 


1,2912 


19.945 


I.184I 


12.088 


1.0587 


3751 


26.594 


I.2843 


19.341 


I- 1734 


11.484 


1,0500 


3668 


25.989 


L2775 


18.730 


1. 163O 


10,879 


1,0414 


3586 


25.385 


I.2708 


18.132 


1. 1528 


10.275 


I.0330 


3505 


24.780 


1.2642 


i7o28 


1. 1428 


Q.670 


I.0246 


3426 


24.176 


1.2578 


16.923 


1. 1330 


9.066 


I.OI68 


3349 


23,572 


I.25I5 


16.319 


1. 1233 


8.462 


I.OO8 I 


3273 


22.967 


11.2453 


15.814 


I.II37 


7.857 


I.0040 



7.263 

6.648 
6.944 
5.540 
4,835 
4.231 

3.626 
3.022 
2.418 

1.813 

1.209 
0.604 
0.302 






ictjuk wxoxaxfc vs. too vis//. ^ 
§ THE END- ? 

OtK i/K VA ten rj(K VA C&X/K VS. V/i 8 



ALPHABETICAL INDEX. 



Page. 
A Concrete Pavement : 

Of what composed 119 

How prepared ...... 119 

How applied 1 20 

A New Cement with Silicate of Soda : 

Merits of 121 

How made 122 

Degree of Heat required to melt 122 

Solidity in boiling water 122 

An Impermeable Cement resisting Steam : 

How prepared 125 

Preparation of Zinc Cement f; \ . 125 

for Foundation Walls 125 

Solidity of 126 

A White Cement or Base for Inside Walls, Breweries and Cel- 
lars : 

How applied 11S 



11 ALPHABETICAL INDEX. 

A Strong Cement for Iron : 

Directions for 133 

Beton Building : 

A Substitute for Brick or Stone Work 136 

Preparation of 137 

Black Paints : 

Suitable for mixing with 105 

Uses of 106 

Permanency of 106 

Blue Pigments : 

Combination with Soluble Glass 106 

Brown : 

Permanency of Color 10S 

Combination with Soluble Glass 108 

Burnt Umber : 

Frequent use of. log 

Combination with 109 

Cocoanut Oil Soap with Twenty Per Cent, Soluble Glass Liquid : 

Action of 146 

Preparation of 146 

Uses and mixtures of 147 

Common Mortar : 

Limestone exposed to Heat \ . 69 

Effect of -69 

Hydrate of Lime as a Cement 69 

Preparation of 69 

Effect of water upon . 70 

Cement and Mortar of the Ancients : 

Comparison of Ancient and Modern Architecture 88 

Opinions thereon 89 

Laws relating to the preparation and use of Lime and 

Mortars < 90 



ALPHABETICAL INDEX. ill 

Cement and Mortar of the Ancients : 

Strength and Durability of some 'pieces of Ancient Archi- 
tecture 91 

Historical Points relating thereto „ 91 

Common Mortar : 

Remarks on 69 

Preparation of 70 

Utility of 70 

Carmine : 

Whence obtained.. 107 

Its relation to Soluble Glass 107 

Cements — The Most Adhesive Lubricator : 

Preparation of 12c 

General usefulness of 120 

Receipt for good whitewash 120 

Cement for closing cracks in Stoves, etc. : 

Preparation of ■. 127 

Cement for a Cistern : 

How prepared 127 

For sweetening the water in 127 

The Best Iron 127 

Colored Cements : 

Preparation of 133 

Coating for Outside Walls : 

Preparation of 134 

Application of ; 134 

Different Soaps : 

Mixture of Soluble Glass with 148 

Various Oils used in 148 

Silicated Soaps 149 

Drying Timber by Steam : 

Experiments with 44 



IV ALPHABETICAL INDEX. 

Drying Timber by Steam : 

Results of 45 

Damp Walls and Cellars : 

Causes of 73 

Prevention of 74 

How applied 75 

Estimation of the Substances with which a Soap may be Adulte- 
rated : 

Table Showing 152 

Notes 152 

German Hydraulic Cement : 

Usefulness of 87 

Preparation of S7 

Remarks on ,..* 8S 

(ire en Paints : 

Combination with 106 

General Rules for the Uses of Soluble Glass : 

Remarks on in 

Glazing of Pottery with Liquid Silicate : 

How prepared 122 

How applied 123 

Beneficial results 123 

Hydraulic Cement : 

How made 70 

Hydraulic Mortar from American Limestone.: 

Of what composed 83 

Peculiarities of 84 

Where found 84 

General remarks 85 

The Kosedale Cement S7 

Hard Adhesive Cement : 

Preparation of 126 



ALPHABETICAL INDEX. V 

Hard adhesive Cement : 

Strength of. 127 

Indian Rtd : 

Combinations of . 107 

Iron Cement for Water and Gas Pipes and Castings : 

How obtained 133 

Utility of 133 

Indian Red : 

Combinations of 107 

Light Red Earth : 

How used k 8 

How obtained .... J08 

Combines with 108 

Luting for Gas Retorts : 

How prepared 121 

Methods of Preserving Wood : 

Cause of decay. 49 

How to prevent 4Q 

Manufacture of Portland Cement : 

When first introduced '. . 75 

Manufacture of 76 

Remarks on 76 

How made 77 

Strength of • 79 

Importance of 79 

Mode of testing 80 

Action of water upon 81 

General remarks 82 

On Mortars and Cements : 

Mortar 61 

General remarks on 62 



VI ALPHABETICAL INDEX. 

On Mortars and Cements : 

Manufacture of 63 

Limestones 64 

Hydraulic Lime 64 

Plaster Cement 65 

Roman Cement 66 

Sand, or Quartz 67 

Rule for making good cement 68 

Painting on Metals, Glass and Porcelain : 

General remarks on 33 

Production of ink 33 

Transfer of colors 34 

Preparation of colors 35 

The ground work 36 

Advantages of 36 

Palm Oil Soaps and addition of Twenty Per Cent. Silicate : 

How used 147 

Receipts for admixtures 14S 

Practical Silicate Painting : 

Preparation for 113 

Remarks on -. . 114 

Red Lead : 

How Employed 107 

Silicate Washing Fluid : 

Receipt for 151 

Silico-Tungstate of Soda : 

How made 151 

Use of , . 151 

Stereochromic for Easel Painting : 

Preparation of 37 

Choice of colors 37 

Remarks on 3S 






ALPHABETICAL INDEX. vil 

Salification of Wood: 

Protection against combustion, inflammability and dry rot. . 39 

Utility of Soluble Glass in this connection. 50 

Various experiments with 41 

Value of 42 

General remarks on 43 

Street Pavements : 

Opinions on 56 

Gene] al remarks on 57 

Silica Paints : 

Fire and water-proof < go. 

Advantages of Soluble Glass. . . 100 

Preparation of. 10 1 

General remarks. , 102 

Soluble Glass in White Paints : 

Composed of 103 

Preparation of 104 

Usefulness of. -.-. 105 

Soluble Glass in Colored Paints : 

Economy « >f . : 105 

Sienna : 

Combination with Soluble Glass. . i 8 

Spanish Brown : 

Frequent use cf log 

Combination of log 

Silica-Black Lead Fire-Proof Paint : 

Combination of 1 10 

Preparation of. no 

Soluble Glass for Black Boards and Silica Slates : 

Usefulness of in 

Preparation, of Ill 

Sol able Glass as a Coating for Wooden Floors : 

Utility of 112 



Vlll ALPHABETICAL INDEX. 

Silicate of Soda in the Production of Gold, Silver and Analine 
Inks : 

How prepared 117 

Advantages of using Soluble Glass 117 

Other inks 118 

Silicate of Soda for Enamel : 

How used 1 18 

Soluble Glass as a Medicine : 

Treatment of Gout or Rheumatism 1 19 

In case of fractures tiq 

Silica Paint for Protecting Ship Bottoms: 

Directions for 131 

Soaps : 

Silicate of Soda in making ■ 137 

Preparation of 138 

Remarks on 139 

Silicate Plastering : 

Benefits of 123 

How used 123 

Soluble Glass application for Various Cements : 

Porcelain, glass and metals 124 

Caseine 124 

Fire-proof cement 124 

The Athens marble cement 124 

Glazed pa^er 125 

Metallic cement 125 

Table for controverting the Areometric Degrees of Baume into 
the specific weights of liquids Heavier than Water : 
Temperature of 153 

Table for the quantity of Caustic Soda in Soda Lye : 

Specific gravity of « 153 

Per cent, of 153 



ALPHABETICAL INDEX. . IX 

The Rosin Soap with twenty-five percent. Soluble Glass Liquid : 

Preparation of 145 

Remarks on 146 

Treatise on Soluble Glass : 

What is Soluble Glass 6 

Its production and usefulness ... 7 

The uses of Soluble Glass, Silicate of Soda, Silicate of Potash, 
and Silicate of Soda and Potash : 

Introduction for architecture. ... 12 

To render wood non-inflammable , 13 

Various uses for its application 14 

Its bright future 15 

Experiments on artificial stone . 16 

Production of hydraulic lime ....... 18 

General remarks. . » ' 20 

Ransome on artificial stone , 23 

The author before the committee of the British House of 

Parliament.... 24 

Experiments and opinions 25 

The Preservation of Wood by Immersion : 

First experiments . . 47 

General remarks .♦ 48 

Timber Rot and Seasoning : 

Causes of . . . . , 50 

How to prevent - 56 

Table of Analysis : 

Remarks « , 52 

The Silicate Hydraulic Cement in the Prevention of W r all Damp: 

Cause of .... 71 

Prevention . , , 72 

The Uses of Hydraulic Cement ; 

Directions for 92 



X ALPHABETICAL INDEX. 

The Uses of Hydraulic Cement : 

General remarks 04 

The best permanent Inerasible Ink : 

How to make 116 

The Cheapest Silicate for Barns and Outhouses : 

Preparation of 121 

The Gypsum and Clay Cement : 

Remarks on .. . . 126 

The Soluble Glass as a substitute for Glue : 

General utility of 129 

Preparation of 130 

The Soluble Glass in Calico Printing: 

Usefulness of 130 

The Most Durable Aquarium Cement : 

Preparation of 1 3 1 

Value of 132- 

The Soluble Glass as manure for Grape Vines and Cereals : 

General utility of 132 

The Silicate of Soda in Common or Household Soaps : 

Hard soaps 140 

Grained soaps 141 

General- remarks 141 

Tallow Soaps : 

Manufacture of 142 

General remarks en 143 

Tallow Rosin Soaps, with thirty per cent, of Soluble Glass : 

How made 144 

Remarks on 145 

Umber: 

Combination with 109 

Utility of ioq 

Umber and Sienna colors ; 

Remarks on in 



ALPHABETICAL INDEX. XI 

Various Soft Soaps which contain fifty per cent, of Silicate : 

Difference between soda and potash soaps 149 

Peculiarities of 149 

Saponification 150 

Green soaps 151 

Black soft soaps « . . . . 151 

Venetian Red : 

Value of 107 

Combination with 107 

Van Dyke Brown : 

Usefulness of 109 

Combination with. . 109 

Wooden Roof Shingles : 

Application of Soluble Glass to 46 

Preparation of 46 

Yellow Colors : 

Preference for 10S 

Combination with 108 

Yellow Ochre : 

General utility of 108 

Combination with 108 



. 



